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24 December 2019

Guns from the Future: the US Army Advanced Combat Rifle Program(1986-1990)

After the 2nd World War, the concept of what an infantryman should carry into battle was changing in vast ways. Gone would be weapons like the M1 Garand, the K98, and the Lee-Enfield Mark IV, that were replaced with battle rifles like the FN FAL and the M14 and the new kid on the block: the assault rifle. America would adopt its first assault rifle formally in 1969: the Colt M16. Developed by ArmaLite engineers Eugene Stoner, Jim Sullivan, and Bob Fremont in the 1950's, the AR-15 was sold to Colt in 1959 and was serious departure from the M14 battle rifle. Advanced for its time, the M-16 would enter directly into war in the jungles of Vietnam. Even at the time of adoption by the US armed forces, there were programs ongoing to find the infantry weapon of the future. However, it wasn't until 1986 that the US Army and USAF would find put the newly updated M16 platform, the M16A2, head-to-head with four next-generation military rifles under the Advanced Combat Rifle Program (or ACR Program). FWS will finally be exploring an interesting time in the history of combat rifles and the M16's history with the ACR Program that ran from 1986-1990. This article has been requested for sometime and it is finally nice to dive into this program. Please note, the H&K G11 caseless rifle and its examples with be explored in much more extensive depth with its own Guns from the Future article in the near future.

The Predecessor to ACR: SPIW, Project SALVO
After World War II, there was a number of studies and research conducted attempting to figure the path for the future of warfare…including military firearms. As early as 1948, there were studies conducted on the future of small arms in the wake of atomic warfare and these initial studies, like Project BALANCE by the Operations Research Office, had started the conversation about flechettes ammunition. In 1952, dueling reports spoke of combat between less than 300 meters with greater need for “pattern dispersion” ammunition and smaller caliber weapon may be able to deliver greater wounding effects and controllable fully automatic fire. In November of 1952, the ORO developed Project SALVO for a controlled volley/burst fire weapon that may use duplex or dart ammunition. During the same time, one of the founders of AAI, Irwin R. Barr was investing into his own personal obsession of flechette ammunition to develop a single flechette cartridge for a next type of infantry rifle. In 1956, government funding came towards developing a single flechette cartridge firing rifle that moved at 4,000 FPS. In June of 1956, the first Project SALVO ammunition were being tested via mule weapons. In 1957, it was decided to move forward with development of flechette cartridges…but, there was no flechette rifle platform yet. The SALVO testing had been conducted using modified Winchester Model 70 rifles.
It was not until 1962 that the military released their goals for their future flechette-firing weapon, along with a new name for the weapon: the Special Purpose Individual Weapon or SPWI. In the winter of 1962, 10 companies had submitted proposals for their own take on the SPWI and that playing field was narrowed down to just four: AAI, Springfield Armory, Harrington & Richardson, and Winchester. The multi-million dollar project was aimed at a next-gen weapon that was less than 10lbs loaded with three grenades and 60 rounds of flechettes. When the prototypes emerged and where being tested in July of 1963, McNamara watched the demonstration and wanted 1,000 prototypes to be made and sent to the battlefields of South Vietnam. This idea was later rejected. In April of 1964, three of the final SPWI candidate rifles were shipped to Fort Benning for testing and the results were not good: none of the candidates were able to move on to Phase II based on mechanical issues. That was not the end of SPWI however. More time and money was given to the project, but by 1966, it seemed that AAI was the only arms company left standing. During this time, the early version of the M16 was making its own path to be the next infantry rifle.
However, the ballooning budget of the program (over $20 million in 1960’s money) caused Congress to investigate the program along with some health concerns associated with the materials used in the flechette ammunition construction. The project was still not dead and it continued onto the 1970’s  that reached its apex in a terrible October 1974 test of an AAI XM70 and an 4.32x45mm XM16E1 Series Bullet  Rifle that saw the AAI rifle fail after just six bursts of fire. That was pretty much the end of the SPWI program, but AAI privately continued on with flechettes with the CAWS project and then their own entry into the ACR Program in 1986. 

The Goals of the US Army ACR Program
The M16 and its second improvement, the M16A2 were still relatively new when the US Army and US Air Force which begs the question: why did was the ACR Program undertaken? Research had shown that the 21st century battlefield required an improved combat rifle that would have greater hit probability during combat stresses at greater ranges. According to statistics included with the ACR Program, an infantryman with an M16 in combat stress condition would only have a 10% chance of hitting a target at 300 meters. Complicating matters was the greater spread of ballistic armor to soldiers at the time. When a infantryman hit their intended target, there was the possibility that effectiveness of the impacted round would be lessened by the body armor that may not even wound the target. One of the requirements of the US Army ACR Program was to greatly increase the hit probability of the rifleman in combat with new advanced ammunition types and firing those new ammunition in bursts/salvos, allowing for more rounds on the target. Thus, increasing the hit probability and lethality over the M16A2 by an increase of 100%. In addition to increasing the hit probability, the ACR Program wanted to increase detection of targets at ranger greater than 400 meters in offensive actions and 1,000 meters in defense operations over the current M16. This was to be undertake by an advance in weapon optics for the ACR candidate rifles. The ACR Program also wanted an improved ACR fire control system that would allow for more effectiveness in all battlefield conditions. Concurrently, the ACR Program wanted to not only develop an advanced combat rifle, but also for that ACR combat rifle to serve as the foundation for a new advanced close support weapon and an advanced grenade system to replace the M203.   

The General History of the Advanced Combat Rifle Program

The Genesis of the ACR Program
In April of 1980, the US Congressional House Armed Services Committee began the ACR Program by asking the Joint Service Small Arms Program office to undertake a study of the current combat service rifle, the M16A1. This Combat Rifle Study (CRS) would return with the M16A1 being still up to standard, however, there was room for improvement. It was that room for improvements found in the CRS  report with the  current M16 that formed the foundation for the requirements for the next combat rifle. The CRS caused the then undersecretary of the US Army, James Ambrose to push for a project to field an improved combat rifle over the M16.
In 1982, James Ambrose endorsed a 10-12 year project timeline to develop an advanced combat rifle with an eye towards caseless and salvo ammunition in association with improved optics. What followed in September in 1982 was the US Army awarding contracts to AAI and Heckler & Koch to explore caseless and salvo ammunition along with optics for these next-generation rifles under the Caseless Ammunition Rifle System (CARS) program. It was under the CARS Program that AAI was working on a 4.32mm caseless rifle that was very similar to the SPWI rifle and the AAI ACR flechette candidate rifle.
During this time, the improved M16, the A2, was classified in November of 1982 while the foundation of the future ACR Program was being laid down. Between the years of 1983-1985, the effort to seek out a next-generation combat rifle to replace the M16 gained traction and speed as the CARS program was folded into the emerging program. Performance goals and meetings were held to put the logistics of the ACR Program into reality. In January of 1985, the Advanced Combat Rifle Program was born.

Phase I (1985/1986)
The US Army issued six funded contracts to some of the most well-known defense companies in the world with the industry alternative program at around February of 1986. However, in the official US Army report issued in 1992, it starts that the contracts were issued in 1985. Those six companies were: AAI Corporation, ARES Inc., Colt, McDonnell Douglas, Steyr-Mannlicher, and Heckler & Koch. According to the document on the ACR Program, the US Army reached out to eight companies, five companies were minimally accepted for a “breadboard demonstrator” presentation of their ACR model at the end of six months. However, it was too narrow of a timeframe and none of the five were able to present their ACR prototype and the government extended the timeframe out to 21 months.  From the official report, H&K was already being considered and was not part of the five “breadboard demonstrator” contracts. At the end of Phase I of the ACR Program, live-fire demonstration and presentations was held along with initial evaluation for the candidate advanced combat rifles. It was here that two of the six candidate rifles were dropped from the ACR Program due to issues with the ammunition and/or mechanical operation of the candidate rifle at around 1987. Dropped were the ARES Industry ACR that fired 5mm caseless rounds and the McDonnell Douglas ACR that fired these oddball “chiclet” rounds that fired salvos of flechettes, almost like a shotgun shell. These weapons will be discussed in further detail below. 

Phase II (1987-1988)
At the beginning of Phase II of the ACR Program in 1987, two of the six were dropped from consideration, leaving us with the “Fab Four”: H&K G11, AAI ACR, the Colt ACR, and the Steyr ACR. During Phase II, it seemed that more tests were conducted to make sure these prototype combat rifles and their exotic ammunition types were safety enough for the rigorous field testing being planned at the upgraded Buckner Range. Also during Phase II was more logistical planning and discussions of the testing parameters of these next-generation combat rifles. On the other end, the companies still in the running were likely improving their candidate rifles and constructing the amount of rifles and ammunition necessary for the upcoming Phase III testing. It was during Phase II that the US Navy and US Marines withdrew their support for the ACR Program in December of 1987 at the Test Integration Working Group.

Phase III (1989-1991)
In August of 1989, Phase III was undertaken with the Fab Four. This was the actually field testing of the Fab Four ACR candidate rifles done at the Buckner Range at Ft. Benning, Georgia in early 1990. The actual Phase III field testing was conducted in itself in three phases that involved different conditions and shooters. Prior to the field testing at the Buckner Range, the US Army and USAF personnel were instructed in the ACR Program safety procedures, testing rules, and introduction to the weapons themselves from July 17th-28th, 1989 at Ft. Benning. While information is limited, I've read that on March 3, 1989, H&K shipped the first 5 G11 ACR cadidates to the Aberdeen Proving Ground. Then in May of 1989, instructors from H&K cam to teach how this advanced weapon worked. Just before the field testing in January of 1990, there was a two day refresher. Each company was required to send 15 ACR candidate rifles along with about 100,000 rounds of ammunition. Besides the Fab Four ACR candidates, there would be 15 standard M16A2 rifles to serve as a baseline, ten rifle optics for use on some of the M16A2, 10 M16A2 that were modified to fire full-auto with muzzle breaks.
For the weeks long Phase III field testing at the Buckner Range, and grueling schedule of weapons testing, that went beyond just firing at targets. The US Army wanted the ACR candidate rifles to be tested as close to combat conditions as possible in a controlled environment during peacetime. To simulate those combat conditions, the field testing was conducted at various times of the day and in various weather conditions. Activities like dispersion fire, hit performance firing were held in conjunction with testing the Fab Four for reliability, maintainability, human factors, safety, and compatibility. During the three phases of testing at Ft. Benning, both male and female shooters were recruited for gathering testing data on how these ACR candidates were handled by the different sexes in combat.
Both the US Army and USAF sent 10 personnel a piece (5 men and 5 women) to fire the ACRs and M16A2s  from standing, prone, and foxhole positions at silhouette targets between 25-600 meters with both iron sights and optics. All manner of data collection methods and machinery was used to make sure that a fair evaluation was conducted. Along with US Army and US Air Force personnel, there were independent contractor-evaluators from Wetzel International to provide another set of eyes on the selection process for the ACR. According to several sources, the field testing portion at Ft. Benning ended at around August of 1990 and the final report was issued in February of 1992 

The 3 Advanced Ammunition Types in the ACR Program

Duplex
What if there was two bullets inside the same cartridge and every time you pull the trigger, two bullets went down range? That idea lead to several experiments with packing an 5.56mm, 7.62mm, and 6.35mm cartridges with two bullets to increase the hit probability with a single trigger pull. That was thinking behind the Colt ACR entry with its 5.56x45mm Duplex ammunition. It makes some sense, but not when put into action. Often the secondary round is a great deal more inaccurate and that is a bad thing in some tactical situations. Then there was increased recoil and expense to the rounds themselves. 

Caseless
Caseless weaponry has been a darling of sci-fi KE weaponry for decades and one of the most famous sci-fi firearms, the Colonial Marines M41a1 Pulse Rifle fires 10mm caseless rounds. Several attempts have been made to develop a caseless combat rifle, with the most serious being the H&K G11 that was the end product of a expensive project going back to the 1960's by Heckler & Koch.
Interestingly enough, there was a 3rd Reich attempted towards the end of the war with developing an caseless combat rifle in 8mm. Four experimental caseless rounds were found in the ruins of Hillerslaben Providing Grounds and interviews with captured officials informed the Allies of an Nazi caseless ammo program that was begin in 1932.
Caseless ammunition has several more advantages over conventional ammunition: less weight. carrying capability, and increased rate of fire due to the lack of need for the ejection cycle. However, unlike conventional ammo, caseless ammo can "cook-off" when the exposed to hot elements of the firearm, the ammo can be brittle and break under some environmental conditional and rough transport. Then were was the complexity factor with caseless weapons as seen in the G11. R&D work into caseless ammunition continues with projects like the LSAT and we could still see yet an military grade caseless weapon in the near future.

Flechette
One of the cool futuristic ammunition types that seen throughout sci-fi is those hypervelocity little darts, or "Flechettes" or even "needlegun". While flechettes have been used on the battlefield since World War I as an air-drop weapon, artillery shells, or in shotgun shells, their use as the ammunition in a combat rifle has been experimental or a limited use weapon like the Soviet APS amphibious rifle. Several attempts have been made to incorporate flechette firing assault rifles into military organizations like the earlier SPIW program and then followed by the ACR program with three entries firing these deadly darts: the Steyr ACR, the failed ARES ACR entry, and the AAI ACR.
These little killer darts have been shown to be grimly effective in inflicting serious trauma along with a relative flat trajectory, but programs that have attempted to develop needleguns have shown needeguns have limited range and lack of accuracy over conventional ammunition. Another issue that was mention in the 1992 report was the lack of tracer flechette ammunition in existence. This was a high priority need if and when the US Military ever accepted needleguns as their standard combat rifle and later on, an LMG.

The “Fab Four” Candidates

The Steyr ACR
For their candidate to the US Army ACR trials, Steyr-Mannlicher of Steyr, Austria sent a weapon that was designed by Ulrich Zedrosservery and stylistically similar to their famous bullpup futuristic-looking 5.56mm assault rifle: the AUG. That the time of the trial, the Steyr AUG was adopted by many US friendly nations as their standard rifle. According to some rumors back in the 80’s, the US Army was also looking at adopting the AUG to replace the M16.
This was the most compact of the ACR candidate of the Fab Four and had the lowest magazine count at 24, but it has the longest barrel due to its bullpup configuration. It was noted by the evaluators having the lowest cost of production in both weapon and ammunition along being simple in operation. The ACR bullpup assault rifle fired a high velocity 1.6inch long 9.85 gain finned flechette projectile from a synthetic casing that was rough the same size of the M16 5.56x45mm round. These SCF darts were aimed by the shooter by either an iron sight or a low-power 1.5x optical sight. One of the standout features of the Steyr ACR was that the flechettes had a velocity of 4,700-4,900 feet-per-second (an M16 M855 5.56mm round travels at roughly 3,100 feet-per-second). For the Phase III testing at Ft. Benning, Steyr sent 15 rifles with 90,000 flechette rounds and it provided to one of the top two ACR candidate rifles.

The Colt M16A2 ACR
Given that Colt was supplying the US military with their standard infantry rifle since the late 1960’s, Colt wanted to keep their juicy government contract and decided to submit their own ACR candidate that looked very similar to the M16A2. It is worth noting that this time; Colt of Hartford, CT was working on the future famous M4 assault carbine, which was in the US Army report as the “XM4”.
For the most part, the Colt ACR looks and functions nearly the same as the M16A2 and this ACR, unlike any other of the ACR candidates, could fire the conventional M855 5.56x45mm standard round. Some of the design of the Colt ACR echoes into today with the M4 carbine like the flattop design and telescoping stock, but there were several elements that separated it from the M16A2: the aiming rib, muzzle break, oil spring buffer, and the exotic ammunition. For the requirements of the ACR Program, the engineers at Colt turned to upgrading their M16 platform to firing an “two-for-one” ammo type: the Duplex Round.
Inside the cartridge casing that was 5.56mm, was two sabots, one that was 33 grains and another that was 35 grains. This had been tried before in an 7.62x51mm duplex round built by Olin Corporation. While seemingly an easy solution to the goals of the ACR Program, one of the Colt ACR rifles actually exploded during use by a contractor due to a jamming in the bore effect. The contractor was not injured, but an investigation was launched. Another interesting element of the Colt ACR ammunition was that all of the duplex rounds were x-rayed to confirm that duplex sabots were in the correct position to prevent issues.  For the Phase III testing at Ft. Benning, Colt sent about 15 rifles with 53,000  Duplex and 10,000 M855  rounds. Interestingly enough, some of the changes/upgrades to the M16A2 via the ACR variant were cited by the ACR Program report as being needed in the next upgrade to the M16, the A3.

The AAI ACR
Until I started on the research phase of this article, I’d never heard of the defense company known as AAI. AAI of Hunt Valley, Maryland, is a major defense aerospace contractor that has been owned by Textron Systems since 2007 and has been involved with the attempt by the US Army to develop a next-generation infantry rifles since the 1950’s with the old SPWI Program. AAI would take the lessons learned from the SPWI rifle candidate and use them to forge their own ACR candidate rifle. In terms of appearance, the AAI ACR is the most traditional looking, calling back to the battle rifles and some elements of the M16. It was also the longest rifle in the test, coming in at 40inches and with a barrel that was 21.3inches. This was slightly bigger than the M16A2 along with being heavier.
This smoothbore rifle fired an saboted fin-stabilized flechette packed into the standard 5.56x45mm casing in either 3-round bursts or semi-auto. This presented several issues with the AAI ACR because the AAI ACR could not fire the traditional M16 5.56mm ball ammunition, like the standard M885 round without critically damaging the AAI rifle, but originally, the AAI ACR could accept regular STANAG M16 magazines. That means in the heat of battle, an shooter could jam an regular M16 mag loaded with regular ammo into the AAI ACR rifle and attempt to fire it with critical damage between done. Thus, AAI altered the magwell of their ACR candidate, preventing the use of STANAG magazines. However, there was nothing prevent a desperate soldier from hand-loading an regular 5.56mm round into the chamber of the AAI ACR.   

One addition to the AAI ACR candidate was the combination sound suppressor/flash hider mounted on all of the AAI needle-rifles. This was due to the massive report and flash when the AAI ACR was fired. According to the information I read, the unmodified prototype rifle was louder than the M16 and had greater muzzle flash. Even with the addition of the suppressor/flash hider, the AAI ACR was still slightly louder than the M16A2 unsuppressed! This could have made the AAI ACR problematic for Special Operations units when the mission required stealth and not direct-action.
For the Phase III testing at Ft. Benning, AAI sent 15 rifles with 90,000 flechette rounds. One interesting one...for the Phase III testing at Ft. Benning, H&K sent 15 rifles with 75,000 flechette rounds.There is something interesting about AAI and flechette ammunition. From the US Army ACR Program report I have, it seems like AAI Corporation was the only one in the USA that could manufacture flechette rifle ammunition due to their involvement in the 1960's SPIW project.On page 10 of Appendix B of the US Army report, it states that AAI Corporation "was the repository of the equipment necessary to product the flechettes needed for both their (AAI) contract and the Steyr-Mannlicher contract and the MDHC (McDonnell Douglas ACR) contract)". 

The H&K G11K2 ACR  

Among the Fab Four ACR candidate rifles that were being tested the summer of 1990 at Ft. Benning, the Heckler & Koch experimental caseless G11 rifle was the most advanced, tested, and risky. For the test, H&K had shipped 15 G11 "Konfiguration 2" or "K2" to the ACR Program field trials along with 75,000 of rounds of the caseless 4.73x33mm ammunition. Oddly, this West German rifle owed its then current existence to the 1981-1988 undersecretary of the US Army: James R. Ambrose. By the time of the early 1980's, the H&K caseless rifle concept was looking for more funding due to the October 1980 NATO STANAG 4172 that adopted the 5.56x45mm round over other contenders, like the H&K 4.7mm caseless round.
The US Army issued an $3.8 million dollar contract for H&K to develop further the concept of  the caseless ammunition rifle system or CARS. This program was folded into the ACR Program in 1986 and things were looking good for the H&K G11. The West German and US Army were both reviewing the bullpup G11 for adaptation, which would solve the company's mounting debt from the G11 R&D costs. Then it all went wrong...but more on that later. By the time the G11 was entered into the ACR Program, H&K had been working on the G11 caseless rifle concept since the late 1960's and was a leader in the field of R&D on caseless ammunition. Not everyone was totally sold on the idea of an caseless rifle for the US Army and if adopted, it would caused a revolution in the types of weapons used. It is highly likely that if the ACR Program trials had put their stamp of approval on the G11 magic space gun, that the US Army would adopted the G11 LMG and 4.73x25mm PDW that were in development for the Bundeswehr as well. The H&K entry into the ACR Program was unique to say the least and it was designed around its advanced and groundbreaking ammunition.
Developed by the West German chemical firm Dynamit Nobel, the caseless ammunition was one of the most difficult elements for the development of the G11. The roughly red-orange box-shaped ammunition was brittle and could crack and break if roughly handled or exposed to hostile conditions. If the propellant was cracked or clipped, the round could fail to load or worse. H&K themselves claimed that the 4.73 DM11 round was waterproof and able to withstand rough treatment. However, to solve any issues, the 51 grain 4.73mm caseless ammo was shipped into the sealed clear plastic containers. The long and skinny 45 round magazines were reloaded by peeling off the seal and placing the ammo reloading case onto the magazine and pressing down to feed the ammo into the G11 magazine. An important note on the ammunition, it is listed as being 4.73x33mm by H&K, but then the G11K2 ACRs shipped to the US were listed as firing an 4.92x34mm round.
I was confused and researched if two ammunition types were developed for the G11. According to the sources online, it was the way the US and Germany differed in the way they measured the ammunition and the ammo are one in the same. The caseless ammunition surrounded the 4.7mm projectile in a block of HMX propellant that allowed for higher rounds-per-minute rate of fire and more ammunition to be carried by the soldier. The K2 variant was designed to allow the rifle to carry three loaded magazines on its front assembly totaling 135 rounds. This would allow vehicle operators and pilots to carry just the G11K2 in their vehicles with three magazines ready to go when they to evacuate from the vehicle in a hurry without having to hunt down ammunition pouches or being limited to just one or two magazines of far less than 135 rounds.
To meet the goal of the ACR Program of putting more rounds onto the targets, the G11 ACR candidate fired a three round burst that delayed the recoil until the last bullet left the barrel. However, as you can see in the gif, the recoil looks brutal and was unlike any other rifle at the time. Interestingly enough, the three-round burst had a higher rate-of-fire than the full auto mode (2100 vs. 460). As noted by many today and even then, the internal mechanism of the G11 was grossly complex to the point of people making jokes that you needed a master's in engineering to service the weapon. In the 1989 manuals issued to the nearly 50 shooters of the ACR Program informed the user of the G11 to stop at a certain point in servicing the weapon due to its complexity. Much more about the bullpup German Magic Space Gun will be covered in a upcoming Guns from the Future article.

The Other Two Candidate Rifles
Both of these candidate rifles were terminated out of the ACR Program around Phase II and well before the Phase III trials (around 1987). Some sources point to the ARES and MDHC candidates are allowed to reenter the ACR Program in October of 1987. However, this means that both the ARES and MDHC ACRs where not field tested against the Fab Four.

The ARES-Olin AIWS ACR
During the initial phases of the ACR Program, the ARES ACR candidate was considered the highest rated of the six candidate combat rifles and the ARES ACR rifle had included all goals of the ACR Program into their design. This weapon was designed by ARES Inc. and the Olin chemical company, which was involved with several other of the ACR candidates. Interestingly enough, one of the heavyweights of the firearms world, Eugene Stoner, designed this drum-fed next-gen combat rifle.
While similar in mechanical function as the Steyr ACR rifle, the unique feature of the ARES-Olin AIWS candidate was its drum-fed plastic-cased 5mm ammunition. The full-telescoped projectile was 5mm and weight in at 45 grains and encased plastic casing of GTX-910. The ammunition was designed and made by the Olin Company, while the weapon itself was made by ARES. ARES and Olin altered the design of the drum-magazine several times and when the weapon was submitted to the ACR Program, it was throw-away non-reloadable 60-round plastic drum that was loaded into the rear of the weapon, making the ARES ACR candidate the one of the two bullpup candidate rifles.
Another odd concept was to have all-tracer ammunition to allow the shooter to adjust their fire during firing. This was the so-called “close loop fire control” and it could not be fully demonstrated at Phase I. The ACR Program had issues with the bulkiness of the drum-magazine and the throw-away nature of it as well. There were issues with accuracy and the ammunition did not achieving “full ballistic performance” at the time of the ACR Program Phase I testing nor the weapon being about to demonstrate the Closed Loop Fire Control tactic. What the 1992 summary cited as the main reason for rejection of the ARES ACR candidate rifle was the plastic ammunition not being stiff enough to prevent jamming and misfire at an unacceptable level.
There were attempts to fix the issue during the testing, but it was unsuccessful and deemed by the ACR Program as a “critical concept defect”. While terminated from the ACR Program, the door was left open for the ARES ACR candidate to rejoin the program if there was time. Unfortunately, the ARES candidate was not able to reenter the program in time and was not evaluated by the ACR Program. The date for this withdraw of the ARES ACR rifle was in April of 1989 and ARES themselves withdrew the weapon due to technical challenges that could not be overcome.

The McDonnell Douglas AIWS ACR
Out of all of the six original ACR Program candidates, the most insane entry and ammunition type was presented by the McDonell Douglas Helicopter Company (MDHC) in their side-loading salvo-firing rifle. The AIWS weapon itself was an “lockless” recoil-operated advanced concept rifle and was designed by Goldin Maury back in the 1970s with work done by James Sullivan in the 1980s. Due to the rarity of information on the MDHC ACR candidate rifle and some issues of clarity, there are mysteries surrounding this entry associated with its ammunition.
We know that originally the MDHC entry had been developed the AIWS in the 1970’s has a salvo-firing rifle that used rectangle-shaped caseless ammunition that was nicknamed “chiclet” that housed duplex or even triplex bullets in 8.6mm in a propellant bed. Due to issues of higher than expected recoil and semi-auto fire mode only, the concept was reworked to have the weapon to fire flechettes instead via the same “chiclet” ammunition concept. Ten of these chiclet ammo packages were loaded into a side-loading magazine, yielding a great amount of firepower.
The timeframe of the switch from bullets to darts is unknown, but it very likely around the time of the beginning of the ACR Program. It is noted in the ACR Program summary that MDHC attempted several different types of flechette ammunition until settling on three darts packed into a .338 cartridge. These flechette-firing MDHC AIWS ACR prototypes were tested again by the ACR Program during Phase II in May of 1988. By June of 1988, the ACR Project dropped the MDHC ACR candidate again, ending their bid. Again, the immaturity of the prototype rifles came clearly through and issues arose due to the complex ammunition that was indeed a salvo weapon, but lacked polish and effectiveness due to the massive technical issues. There was also aiming issues with the flechettes, including that none of the deadly darts were on target in short distances and even more problematic in longer distances.    

The Outcome of the ACR Program 
Since the US armed forces is still using the M16 assault rifle today in 2019, you can safely assume the outcome of the $300 million US Army tests to locate a possible candidate or an technologically avenue to explore to replace the M16A2. While each ACR candidate rifle did indeed offered something new and inventive to the table in late-1980’s strategic thinking. The trial was held in summer of 1990, at the Fort Benning with USAF and Army personnel involved putting the Fab Four and an M16A2 through their paces at Buckner Range, which given an expensive and extensive makeover just for the ACR Program trials. It was hoped that the Buckner Range would replicate as-close-as-possible conditions to combat, allowing for an honest and effective test of both the ACR candidates as well as the new weapons munitions technology on display. According to several articles I read about the outcome of torturous combat trials at Fort Benning, the M16A2 still did very well against the next-generation candidate rifles, but none of them, including the M16A2, achieved the nearly impossible 100% increase hit probability desired by the ACR Program goals.
While the developers of these weapons and the Army brass may have thought the $300 million project was a waste, the official ACR Program summary stated that in someways the ACR Program was a success in showing how far these exotic ammunition types had come since earlier programs and tests. In addition, the report speaks glowingly of the field testing itself and the surprising success of the baseline M16A2 in the field trials.
That being said, for the time being, the US Army would stay with the M16A2 platform and move in another direction to increase lethality and hit probability.
It was concluded by the Army Infantry School upon completion of the ACR Program final report that explosive ammunition would be the path forward to achieve the goals and this resulted in the Objective Individual Combat Weapon Program that yielded the H&K XM29 OICW weapon. FWS will be covering both the weapon and program in a future installment of this series. While each one of the ACR candidates was praised for different elements of their design and ammunition, there were serious issues with all of the Fab Four that prevented any forward movement with any of the Fab Four or their ammunition. Many articles online gloss over the final results in very overview prospective, however, I wanted to know more about the actual results and how each candidate gun fared in the Phase III field trials. Here is what I found out:

The Steyr ACR Final Verdict
According to the US Army's final summary report from February of 1992, the Steyr ACR candidate was well-liked by the US Army and USAF shooters, but while the weapon itself was well received, the ammunition was not. The flechette rounds were worse overall than the standards set by the ACR Program test guidelines in the three firing ranges tested (short, intermediate, and long). It did not matter if it was semi-auto or full-auto fire and it got even worse when it came to the long range shooting (less than 10%). However, at short range, around 25 meters, the Steyr ACR did very well, and it really shined in the 50 and 75 meter range testing with full-auto and semi-auto fire with had the higher hit probability than the standard set by the M16A2. After this, the result became much worse. Some modifications were made to the flechette ammunition of the AAI and Steyr candidates by shortening the darts by 0.10 inches. This caused less tumbling and less lethality than previous test results.
There was much praise in the summary for the low cost per unit for the Steyr ACR, which was even lower than the current price tag for the M16A2 (by 40%) along with the simple mechanical design of the weapon over the H&K G11 ACR. During the first phase of the ACR Program, the report makes mention of safety concerns that were solved, but the Steyr candidate was nearly thrown out of ACR Program around Phase I, much like the other two rejected candidates. From other sources I've read, this may have been due to an critical issue with cracking and manufacturing inconsistencies in the plastic cases of the flechette ammunition, causing performance and safety issues. It is worth noting that Steyr themselves were unhappy with the quality of the flechette ammunition and believed that was part of the causes with the performance of their ACR candidate weapon in the trials.
Cited in the 1992 summary ACR report was the poor dispersion performance of the flechettes from round-to-round that could be off target by generally 1.0 mils with the worst being 1.75 mils. This was noted as being a hazard to friendly troops during larger infantry engagements and a major issue to hitting enemy targets at even moderate ranges, especially when matched head-to-head with the standard M16A2 M885 round that far outperformed the flechettes in both the Steyr and AAI ACR candidates. Another downside of the dart ammunition in both the AAI and Steyr ACR candidates was the lack of developed tracer or blank flechette round. It is also funny to read in the context of the M4A1 carbine being the US military standard combat rifle today, is that ACR summary report says that the Steyr ACR candidate is nearly too small (nearly 10 inches shorter in length than the standard M16A2) for being a standard combat rifle! 

The AAI ACR Final Verdict

The relationship between the US military and AAI developing future guns goes back to the 1950's, when the SPWI project was attempting to develop an needle rifle and more recently when AAI attempted to developed an caseless rifle for the CARS program and it made sense that AAI would be one of the companies given the green light to enter the ACR program trials. Due to the similarities in ammunition to the Steyr ACR candidate, the 1992 ACR summary report lumps them together and so, I'll be repeating myself with the results here. The flechette rounds were worse overall than the standards set by the ACR Program test guidelines in the three firing ranges tested (short, intermediate, and long).
It did not matter if it was semi-auto or three-round burst fire and it got even worse when it came to the long range shooting (less than 10%). However, at short range, around 25 meters, the AAI ACR did very well, and it really shined in the 50 and 75 meter range testing with burst fire (the AAI ACR did not possess full-auto fire mode) with had the higher hit probability than the standard. After this, the result became much worse. Some modifications were made to the flechette ammunition of the AAI and Steyr candidates by shortening the darts by 0.10 inches. This caused less tumbling and less lethality than previous test results despite the high velocity (4600 ft. per second).
In the summary, the AAI ACR candidate rifle was considered the most "mature" than any of the other weapons and the was praised leveled at the AAI ACR traditional design and handling along with overall reliability under the stressful condition of the Phase III field testing. The ACR Program report even stated that another look should be given, if caseless ammunition was selected as the technological path to be explored, at another H&K/AAI partnership to marry the West German caseless ammunition to the AAI rifle. This would have been an "sequel" to the 1982 CARS Program. Lastly, another downside of the dart ammunition in both the AAI and Steyr ACR candidates was the lack of developed tracer or blank flechette round. Another flaw that haunted the AAI candidate rifle was that it could not fire normal non-flechette 5.56mm rounds, but looked like it could and if desperate, the soldier could hand-load an M855 bullet into the weapon and fatally damage the AAI ACR. 

The H&K G11K2 ACR Final Verdict
If there was a real star among the candidate rifles, it was the H&K G11K2. There was nothing like in the 1980’s and that even holds true today. It was the weapon that had the most to prove and it was the most complex. Simply put, the G11 had been in development since the 1960’s and this futuristic caseless rifle represented a serious dollar amount to a major arms company and several governments. This means that a great deal was riding on if the West German and US government would issue multi-million dollar contracts for the G11, the ammo, and its variants. In the 1992 summary report issued by the ACR Program, there more written about the G11 than any of the Fab Four. However, in the actual testing data, there is very little said about the G11K2…which is odd. However, the further information on the ACR Program thoughts and data on the G11 was in Volume IV and Volume VII of the final report documents and those are not accessible to the general public.
So, some of the information on the final evaluation was in the Volume I summary report and some was taken by reading between the lines. H&K sent 15 G11K2 rifles to Ft. Benning for the field testing, along with 75,000 “4.92mm” caseless rounds and some H&K technical advisers. US Army ACR Program had reservations about the cook-off factor and survivability associated with caseless ammunition and the complexity of the weapon itself.  To satisfy the need for their own data, the ACR Program subjected the 4.73mm caseless ammo to their own batch of test. The CSTA portion of the ACR Program fired 100 rounds through the G11 and waited to see if the 101st round cooked off…and it did not. This impressed the ACR Program evaluators and they stated clearly that “the feasibility of a caseless ammunition rifle system has been successfully demonstrated with this effort”.
During the torturous testing at the Buckner Range, the G11K2 did not have any failures during thousands of rounds fired and interestingly, 80% female shooters failed to quality with the G11K2 and was chalked up to limited hands-on time with the magic German space gun. For the short-range hit probability test, the G11 ACR candidate did extremely well, and came to the line set by the M16A2 standard, but never exceeded it in both burst and semi-auto fire modes. When it came time for the long-range hit probability shooting trials, the G11 ACR came up short compared to the M16A2 standard, and was called “statistically worse” than the M16A2.  For the intermediate range, the G11 did worse than standard when fired in semi-auto (likely due to the recoil) and with the low-power optical sight (there was no G11 iron sight...sorry Black Ops). This was also true of the caseless weapon being fired in burst mode in the intermediate range testing.
It was concluded by the test results that the G11K2 performed better in burst fire mode than semi-auto, which was in direct contrast to the M16A2. Overall, the G11 was not a match for the M16A2 standard. However, at 75 meters, the H&K was better than the standard in burst. As with all of the ACR candidate Fab Four, the G11 did not meet the 100% improvement threshold, but impressed the ACR Program overall with the efforts of H&K and Dynamit Nobel (who formed a consortium in West Germany for the caseless ammunition. So H&K made the weapon and the DNAG consortium made the ammo). From reading in-between the lines in the 1992 summary report, you gather why the mature G11K2 ACR candidate was not moved on down the line to being the next US Army/USAF combat rifle.
In September of 1982, the US Army issued contracts with AAI and H&K to develop a caseless combat rifle under the CARS program. CARS morphed into ACR in 1986 and those two companies were folded into the ACR Program. At the time, the G11 was well known in the realm of military technology and NATO, and it makes sense that the US Army tapped H&K to develop caseless ammunition. However, while the ACR Program was sold on the caseless ammunition that the G11K2 gave them more of the salvo-fire concept they were looking for, it was the weapon itself that may have bothered the Army brass. Another goal of the ACR Program that the G11K2 could fulfilled was the Advanced Close Support Weapon in the G11 LMG.
While it is clear that the G11 is a complex mechanical marvel that was a groundbreaking weapon, it was expensive and mechanically complex. It seemed for the hints in the ACR Volume I report that the ACR Program leadership were concerned about the internal complexity of the G11 and the company-imposed limits of field-stripping ability by a infantryman. There was also concern over the ergonomics and even the style of the chunky science fiction looking weapon. The most damning final verdict by the ACR Program on the G11K2 appears on page 3 of Appendix B: “for future purpose, the melding of the AAI mechanism with the highly superior H&K (HMX) propellant might conceivably result in a weapon superior to both candidates”.

The Colt M16A2 ACR Final Verdict
The odduck of the ACR Program Fab Four was the Colt ACR due to the ACR being based on the then-current M16A2, but with platform modifications and a new type of ammunition: duplex. It also interesting that unlike any other of the Fab Four candidates, the Colt ACR could fire the standard M885 5.56x45mm round with no issues...and the Colt ACR had to fire the M885 cartridge under long-range shooting conditions. When the normal M885 ammunition was fired through the Colt ACR, there was no difference in performance over a conventional M16A2.
The Olin Corporation made duplex 5.56mm round was based on their previous duplex 7.62x51mm round experiments and it performed better than the flechette rounds, but there was a major downside: range. According to the 1992 summary report, the user of the Colt ACR would have to switch from their futuristic duplex salvo ammo when engaging targets over 325 meters. This translates to soldiers being forced to carry two different kinds of ammunition into battle and switching  the ammunition based on the range of the targets during combat. The ACR Program looked dimly on this, but the Colt ACR was one of the two candidate rifles that actually delivered on the promise of salvo fire.
According to the 1992 summary report, the duplex ammunition preformed better than standard in all of the ranges tested. At 150 and 300 meters, the heavier-than-M885 duplex ammunition did very well and bested the other three candidate rifles. However, when the range increased above 300, the report discusses quick degraded of hit probability due to the lighter mass of the two projectiles in the duplex cartridges.
Despite some promising test results and the Colt ACR being based on the current US military combat rifle, the ACR Program did not want the future infantryman to be forced to carry two different types of bullets into combat then switch in the middle of a gun battle between the different types of rounds. However, the duplex round at short range did increase hit probability with a salvo spread. Two other elements that likely worked against the Colt ACR is the explosion of one of the rifles during testing of the duplex ammunition with the trailing projectile becoming lodged in the barrel and that the duplex 5.56mm round was heavier than the standard M885 round; adding to the soldiers burden in the field along with logistical challenges.   

What Happened to the Fab Four after the ACR Program Ended?
After the field testing and the data was collected and analyzed, none of the Fab Four or their munitions technology as accepted by the US Army. But is that the end of the story for these advanced rifles? What happened to these rifles after the ACR Program? As to the whereabouts of the actually rifles issued to the ACR Program during Phase III, most were returned to their respective companies to suffer various fates. Some were put into museums or display walls and others may have been destroyed or boxed. As to the technology explored and developed for the candidate rifles, only the caseless ammunition by H&K and Dynamit Nobel would be licensed for use in the Lightweight Small Arms Technology program that many of us know of due to the LSAT inclusion in Black Ops II. The jury is still out on if caseless ammunition firing combat rifles will ever be the replacement, but certainly, the H&K G11 was the pathfinder to any future caseless ammunition projects. The duplex ammunition submitted by Colt was never continued after the ACR Program as was the flechette ammunition. Since the 1950's, there has been a common thought that flechette ammunition would be the future of KE weapons.
However, the ACR Program field trials have shown that while these little HV darts could inflict gruesome damage, they did not have the range to be the primary ammunition of a combat rifle and there were safety concerns as well to friendly soldiers. Oddly, from time-to-time, a few of the prototypes from the ACR trials pop up for sale. One of these cases of a prototype rifle was an Steyr ACR with four rounds of ammunition owned by former DELTA Operator Larry Vickers. A few years ago, he attempted to sell his Steyr ACR for around $10k-$12k. Recently, an Colt ACR popped up for sale with two boxes of duplex ammunition. If you zoom in on the boxes of ammo, you can see that they were stamped with "PHASE II TESTING" on them with a production date of "3-23-88". Sadly, you needed a Class-III license to buy it and $75,000.

What If...the US Army had Adopted One of the ACR Candidates?
So, it is time to play the game of "What If..." and imagine in this scenario of this alternate universe where one of the ACR candidates was adopted as the official US Army service rifle in 1996. Just after the ACR Program ended in 1990, the US Military fought its first war since Vietnam with the Gulf War in 1991, and this could have or did change the thinking on the ACR candidate rifles and could have affected the adaption of this next-gen rifle. If the US Army and Air Force had selected an ACR candidate rifle, let us say the H&K G11 for example, it would have changed the way that other nations would have looked at caseless ammunition and possibly changed the course of military small arms history.
This happens in the realm of military hardware all the time, when one major nation adopts a new concept, others follow and the US military fielding the G11 would have altered the global thinking on caseless ammunition and it could have lead to the newly unified German government to not abandon the G11 for their own troops. This could altered the flow of history for military small arms development and allowed for the G11 variants, the PDW and LMG, to be constructed. Instead of the AR15/M4/M16 platform being the trendsetter in the current world of military small arms and civilian firearms market, it could have been the G11/caseless ammunition. That could have meant that the weapon that would have gone to Afghanistan, Iraq, and Syria could have been the G11. That also means that the weapon that could have killed UBL would not have been an H&K 416, but instead an H&K G11. Of course, just because the Big Army and the USAF got onboard the ACR train does not mean the USMC, USN, and SOCCOM would have followed. Given the brutal conditions that the new next-gen combat rifle would have been subjected to in the War on Terror battlefields could have meant the rejection of the new rifle or issues as we saw with the M16 when it was issued in Vietnam. The ACR rifle could have failed under these condition and the military would be left with a real mess.
Then there is another issue: the American civilian firearms market. Unlike most of the world, in the United States, you can own a military rifle that is often better quality than what the warfighters use in actual combat and if you have the right paperwork and tax stamp, it can be full rock-n-roll. That being said, the majority of weapons sold in the US are traditional bullet technology and calibers...but, would that have applied to the ammunition tested in the ACR Program? While flechettes are ban in some states, there has never been a needlegun to challenge the laws on the books, and there was some caseless ammunition firing weapons sold on the US market, like the 1968-1969 Daisy V/L .22 caseless rifle.
To me, I don't think there has been a true test of the US firearm and ammunition laws when it come to futuristic KE and DE weapon technology. For example, in The Forever War, William could not buy a laser for protection, but all manner of more traditional weaponry (including flechettes) were legal to own and carry. If and when the US military adopts something other than traditional bullets and the firearms company attempts to make a civilian-legal variant, then we could see the the law challenged in the courts and legislative body. There was some legal challenge to the Gyrojet weapons made by MBA in the 1960's by the 1968 Gun Control Act, and even a court case involving some Gryojet museum pieces. This legal challenge caused MBA to construct a Gryojet Mk. II that fired a .49 rocket. However, once again, it should be take under consideration that the MBA Gryojet was a flop and made little impact in the firearms and legal world. If the concept had been a success than maybe there would have been more of a legal challenge.         

Why Hasn't the US Military Not Replaced the M16 Yet?
At this point in 2019, the Colt M-16 is now the longest serving US Military infantry rifle in its history. In addition, it was the first assault rifle adapted by the US Military as well, making the M-16 an interesting modern military rifle. Unlike many other early assault rifles, the US Military is still not widely replaced the M-16 and oddly, other nations are starting to adapt the improved versions of the weapon that Eugene Stoner developed in the late 1950's while at Armalite.
To me, given my knowledge of the history of the M-16 and how it was thought of by Vietnam Vets in the 1980's, it is deeply vexing to see the current white-hot love affair that the M-16 is having with the American civilian shooter market, American Law Enforcement, and international military organizations.
Many times over the course of the 1980's and 1990's, I heard from some gun magazines that the US Military was going to replace the infamous black Mattel rifle with something else...but, that never happened. That begs the question, why hasn't the M-16 been replaced with something else? Part of the discussion we are having here on FWS with the story of the ACR trials is why the M-16 was not replaced, and thought I should provide some reason why the M16 is still the US Military's standard combat rifle. With the disaster that the rollout of the M16 was during the Vietnam War, there was talk of the US Armed Forces replacing the weapon very early on into the M16's history. Some unit in Vietnam broke out their old M-14 battle rifles or stole AK-47s and Type 56s off the bodies of dead NVA/Viet-Cong soldiers. This was a valid solution to the issues with the new M-16 that had fatal jams and failures that caused the deaths of US soldiers. Some soldiers died next to their broken down M-16 and this prompted an Congressional investigation by the House Armed Services Committee into the failures of the M-16 on the battlefield of Vietnam.
During the post-Vietnam funk, the M16 was still around, but there was research beginning on a possible futuristic replacement. During the Reagan Administration, there was money and interest in improving the M16 with the M16A2 in 1986, but also there was serious money being invested into the next-generation small-arms weapon system with the ACR Program. At the time, there was talk in the firearms magazines of rumors that the US Armed Forces were looking seriously at the Steyr AUG as a short-time replacement before laser rifles or some other damn thing were developed.As we know, the ACR Program was not able to select an next-gen rifle that could be a marked improvement over the M16A2. Thus began the Objective Individual Combat Weapon program that yield the futuristic XM29 OICW...which FWS will be discussing in a upcoming Guns from the Future article. Once again, the M-16 hung on through the ACR and OICW program and outlived them.
During the current War on Terror as the M4 carbine was becoming a star of the new war, while there two serious replacement not-as-futuristic concept assault rifles on the horizon with the H&K XM8 and the FN SCAR. While on of the FN SCAR variants, the SCAR-H became used in limited numbers by members of the US Special Operations community, the H&K XM8 came close to be the next generation assault rifle for the US Military. Once again, the M16 in the form of the M16A4 and the M4 march onward during a time of war. It was also during this time that the general American public became obsessed with the AR15 assault rifle and sales jumped to unseen levels along with all manner of manufacturers creating improves to the aging platform.
In some ways, as some will argue, the M4 and the H&K 416 are the real replacement for the M-16. However, the stellar H&K 416 is based around the designs and ergonomics laied down by Stoner & crew in the 1950's. This more an evolutionary step not a great leap forward. The lengthy section above is meant to give us some of the interesting history of the M-16 and to answer some of the certain question...but there are other reasons why the M16 still has not been replaced. In some ways, the M16 has become a symbol of America, the American gun industry, and the versatility of an firearms platform. The M-16, as one of my coworkers observed, as a certain gravity or inertia towards it that has drawn American gun owners and even the Paintball/Airsoft market into the Church of M-16. After a poll at my hospital unit, about 80% of the RNs own an AR15 assault rifle. 80%. Growing up, I knew 2 people that had an M-16. Two.

Sci-Fi and the ACR Program
On the surface, it may not seem that the US Army Advanced Combat Rifle Program of the 1980's had much if any impact on the realm of science fiction...however, I think there some echos of the ACR Program to be explored. At the time, there was a number of publications devoted to exploring the world of firearm, military hardware, and technology, like International Combat Arms. Creators of all type and genres used these resources to investigate what future soldiers would be armed with and programs like SPWI, and ACR helped give creators a pathway. High profile weapons like the H&K G11 also helped forward the profile of the ACR Program and caseless ammunition to the point that caseless ammunition became a hallmark for military science fiction works like the M41A1 Pulse Rifle from ALIENS. At the time as well, tabletop gaming was apex of popularity and the companies, like FASA, that pumped out source material needed ideas to full those pages. One such example is the FASA Battletech Technical Readout 3026 from 1987 that seems to have used the ACR Program Fab Four as a source of inspiration for the small arms of the Inner Sphere. Then people exposed to those examples from the FASA technical manual, like me, then use it as inspiration for their own and so on. In addition, due to the futuristic design to the Fab Four, the weapons themselves were used by creators to pattern their own fictional futuristic weapons after, like the Evangelion pellet rifle that was directly lifted from the Steyr ACR candidate or the AcMag from the Demolition Man. With the age of the internet, the ACR Program and the candidate rifles have been given a second life and able to reach more creators. 
    
Examples
At a glance, it would seem that only the H&K magic Kaut space gun, the G11, would have entries on here. However, after some painstaking research by myself and Yoel, we have come up with some examples outside of the G11. Please note, we limited the number of G11 examples and the full list of those G11 examples will be explored in its own article.

The Steyr ACR from The Punisher War Journal
During the late 1980's, I collected something rare for me: an actual "superhero" comic. I was not much for the traditional superheroes comics, but I was drawn into the pages of the original Punisher War Journal and I think these are the best comics about Marvel's anti-hero, Frank Castle. In the back pages of the War Journal was a single color page called "the equipment page" devoted to a real-steel weapon or some tech along with the thoughts of the Punisher on this weapon or item. Amazing script and art by Eliot R. Brown made this element come alive and it was one of my favorite sections of the comic book. Some of my first exposure to some weapons was here, like the FN P90 and the subject of this article: the Steyr ACR. Lovingly laid out and explained in a Marvel Comic is the flechette firing futuristic ACR candidate rifle along with Lost in Space. Frank dives into the weapon's ammo, data on the darts, and how he hopes the US Army will approve the weapon because he needs more ammunition and he would have to go back to Germany to get it. Of course, the script is wrong on that account and the Steyr is Austrian, not German, and the ammunition was made here in the USA by AAI...if the 1992 summary report is to be believed. Due to the nature of scanned older comic books online, attempting to find the issue that this appeared has been difficult. However, the Steyr ACR entry was included in third issue of the The Punisher Armory series.  

The Colt ACR from "Action Man Mortar Combat Mission Raid" 2002 Figure
In America, the Action Man line of toy soldiers is more unknown due to it being a British creation that based on the American GI Joe action figures of the same time. Palitoy began their Action Man toyline in 1964 and two years later, the first plastic toy soldiers were released. Much like the Hasbro GI Joe toyline, the Action Man toyline has popped in and out of toy shelves over the course of its history. In 1993-2006, Hasbro relaunched the toyline with more of an action/adventure theme rather than straight military. During this time, one of the more military figures produced was "Mortar Combat Mission Raid" in 2002 that featured a mortar soldier with the only example of the Colt M16A2 ACR. Found by chief FWS contributor Yoel, this toy soldier is armed with an Colt ACR. It is madding to see the only example of the Colt ACR out of the context of the ACR Program with no explanation and no further information on why this ACR candidate rifle is there. It just exists in his plastic hands and Action Man is not saying a word about his super rare ACR. The odd thing about the Colt ACR in the figure is that there is no magazine in the weapon, but Hasbro included the optic and something mounted under the forward assembly of the rifle. Maybe one day, we'll get an answer on the inclusion of this weapon. A big thank you goes to Yoel for locating this one!     

The G11 "Guerrilla Rifle" from Rhea Gall Force
The long running military science fiction anime and manga series Gall Force, we see the German magic space gun in the hands of the guerrilla forces along some weapons based around the G11 such as Norton's G11-like handgun. In the 1988 OVA Rhea Gall Force installment, it is 2085 on the planet Earth and some of the ancient alien technology is found on Luna during World War III. It is believed that the best option for humanity is to evaluate to the Mars base. The G11 appears to be no real different than the real-steel G11 in both operation and ammunition, but it was not used by any of the main Rhea Gall Force characters.  

The GI Joe XMLA-3R Laser Rifle from the GI Joe: Real American Hero
For weeks, Yoel and I searched for an example of the AAI ACR flechette rifle to include...and we came up with nothing. However, I firmly believe that the standard issue laser rifle, the XMLA-3R, in the GI Joe: Real American Hero cartoon series was based on the earlier AAI SPWI entry, that was also very similar to the AAI ACR candidate rifle. According to information on GI Joe fansites, Ron Rudat was a Hasbro artist/designer and was tapped to work on the toyline and the later the cartoon by the head of the GI Joe: Real American Hero: Bob Prupis.
The staff on the GI Joe relaunch project embarked on a great deal of research, including field trips to Natick Army Labs in Massachusetts, which had examples of the AAI SPWI flechette rifles. Some of what they saw was incorporated into the designs of the weapons that the soldiers carried in the toyline and TV series. This maybe were the XMLA-3R laser rifle basic design originated from, however, I cannot find any concrete evidence. The first appearance of the XMLA-3R was with the original Snow Job figure released in the second series of the Hasbro GI Joe: Real American Hero figures and vehicles. Mentioned in the data card was the name of the laser rifle that was in the packaging. Around this time, Sunbow/Marvel developed a TV mini-series around the MASS Device that aired in 1983 and featured laser DEWs in the hands of COBRA and the Joes. The standard issue laser DE rifle for the GI Joe team was the same as the one included with the Snow Job figure: the XMLA-3R. When a full series was ordered, the XMLA-3R continued to be the standard Joe laser rifle. If indeed the XMLA-3R is based on an AAI rifle, it is likely the SPWI candidate or some other AAI prototype, but not the AAI ACR in the ACR Program trials due to the timeframe. The GI Joe series was already wrapped up by the time the general public knew anything about the AAI flechette rifle.         

The Standard Suit Rifle from Uchū no Senshi
In 1988, Sunrise and Bandai Visual would release Uchu no Senshi (or “Cosmic Warrior” in English) in a three part Laserdisc release-only format that was based on the iconic 1959 Starship Troopers novel. The LaserDiscs were never released to the West and much lore and mystery was constructed around this SST anime. Given the amazing armored powered suit design by mecha master artist Kazutaka Miyatake, the APS from Uchu no Senshi became famous and in the hands of some of the CLASS-II powered armor was the standard suit rifle that was loosely based on the H&K G11, right down to the overall blocky design, the magazine placement and replication of the caseless ammunition.

The Pellet Rifle from Evangelion Universe
One of the most popular mecha-based animes of all time is Neon Genesis Evangelion and it is odd to think that among the interesting mecha that populates this universe is one of the rare examples of the ACR Program candidate rifles...the flechette-firing Steyr ACR. Styled nearly the same as the Steyr ACR, but supersized for the scale for the Evangelion mecha, specifically Unit 00, 01, and 02. While there is little information on why it is called "the pellet rifle", there is some sources that state in the Evangelion: 1.0 You Are (Not) Alone movie, it is said that the Pellet Rifles fire an 209mm caseless projectile. Unlike the real-steel Steyr ACR, the Pellet Rifle does not possess a plastic magazine, but rather an all metal magazine that looks more like it should be on an directed energy rifle of some sort. Given the Pellet Rifles appear in this popular franchise, the Pellet Rifle has been featured in models, toys, and video games. For the record, the H&K G11 can be seen in the hands of some soldiers in the Evangelion anime.        

The Magnetic Accelerator Rifle from Demolition Man
The most famous, but not the first appearance of the H&K G11 in a visual production was from 1993 American film Demolition Man. In the sci-fi action film, criminal Simon Phoenix raids a future history museum for weapons, due to the peaceful nature of the future 2032 society. During the raid, he wonders aloud if this is indeed the future, then were are all of the phaser guns? In a display case is a futuristic soldier equipped with an advanced firearm known as the "Magnetic Accelerator Rifle" or "AcMag"and it was, said by the computer, to be the last hand-held weapon. Listed by the computer display as an kinetic energy weapon, but then lists the data for the real-steel G11 down to its caseless ammunition. Just below the weapon on the computer screen is more information on AcMag, like that it has 700 rounds when fully loaded and a range of 800 meters.
This was likely a close-quarters/urban combat particle beam weapon that represents an early stage of the technology given the charging time for the weapon between shots. In the film, the computer explains more to Simon about just what the AcMag (as it is called in the film) is due to his question on its operation (this text is taken from the shooting script): "The Magnetic Accelerator gun, the last produced handheld weapon of this millennium displaced the flow of neutrons through a non-linear cycloid supercooled electromagnetic force. The AcMag, now reactivated, should concurrently supercool and achieve fission in...two point six minutes". The conflict between the two displays of information comes from simple production mistakes. For the production of the film, the G11 is a cast prop from armourer Michael Papac based on a loaned G11 prototype from H&K themselves. H&K had to be directly involved with the plans for the weapon in the film and even took the "futured-up" prop used for Demolition Man at the end of filming.

The Steyr ACR in Black Ops: II?!
About the time that Black Ops II was about to be released and the COD rumor mill was running overtime, it was the apex of popularity for the shooter franchise. During this time, I heard rumors that another ACR Project candidate, the Steyr, was coming to the COD family, the first being the H&K G11 Magic Space Gun in original Black Ops video game. There were message board posts and YouTube videos, but it was not true. The weapon that some were thinking would be the Steyr ACR was actually the Type-25 bullpup assault rifle. While an interesting rumor, I wished it had been true. It would have been cool to have the Steyr ACR in Black Ops II.

Agent Helix's G11 from GI Joe: Rise of COBRA toyline
One of the newer GI Joe characters in the toyline and comics is Agent Helix, who is an covert intelligence officer. Her action figure was released in 2009 for the Rise of COBRA line and came with a number of weapons. In the comic and artwork, Agent Helix is often depicted with a pair of auto-pistols that appear to be based on the 9mm Glock G18. However, for the action figure of Agent Helix, she is also equipped with our old friend, the H&K G11. As far as I can research, Agent Helix has never been depicted wielding an G11 magic space gun. This is similar to a few other GI Joe figures, like COBRA Commander, being outfitted with a G11 as well.
The Sources:

1. Future Weapon by Kevin Dockery, published by the Berkeley Group in 2007

2. The ACR Program Volume I Summary by Vernon E. Shisler and Stephen M. Mango, published by the US Army Armament Research, Development, and Engineering Center in February 1992.

3. Forgotten Weapons Youtube Channel by Ian McCollum

4. The Armourers Bench web-article series on the ACR Program weapons


Next Time on FWS...
We will be returning to one of the best loved serials on FWS: Ships of the Line! In the next installment of this series, FWS will be exploring and explaining the realm of smaller warships that are involved with nontraditional space naval warfare like Raiders, Marauders, and Gunboats.