22 July 2015

FWS Armory: Belt Fed

When continues and rapid power are needed it's time to drop your carbine and open fresh box of ammunition belt. This string of deadly pearls had been feeding machine guns from late 19th century till nowadays. From the Maxim guns mowing charging infantry in the trenches of WW1 to the modern SAW (Squad Automatic Weapon) in the hands of infantrymen in the streets of Fallujah or Rafah, those belt feds have been an active player in all of humanity conflicts in the 20th ; But will they be with us in the future? In this new FWS Armory article we'll examine the ammo belt from top to bottom and separate the fiction out of the SF.    

Advantages of belt over magazine

Round capacity
While most rifle magazines are limited to 30-40 rounds the ammo belts usually contains more than a 100 rounds for the smaller ammo boxes and doubled, tripled or more for the bigger one.
Having a bigger 'gas tank' means your gun can fire more rapid fire and longer time between one reload to another.





Continues fire
Unlike magazine that opens from one end the belt is 'opened' from both sides, holding the stick from both ends if you will… While one end was inserted to the gun the other end can be coupled to fresh belt, practically extending the belt length without replacing the belt currently in the gun. One of the coolest aspects of this ability is that the belt could extend while the gun is firing! Medium & heavy machineguns are operated using more than one operator. When one operator aim & shoot the other/s provide fresh belts either to reload the gun with new belt or to coupled new belt to the old one.    

Clear ammo status indication
Magazines are usually opaque metal boxes and the shooter can't usually see when is magazine is near to "draw its last breath". With belt the shooter can clearly observe his/her ammo status cause the path of the belt from the box to the gun is usually expose and when the belt is nearly all consumed the remaining rounds are visibly indicates it's time to reload.



Disadvantages of belt over magazine

Complexity of the belt
The complexity & fragility of the belt links is the Achilles heel of the belt fed gun. As they say "the chain is as strong as its weakest link" – 300 rounds belt have a 299 potential weak links, add to that the rough conditions those guns usually endure and you relies that problems are always an issue. The common malfunction is breaking of one link in the belt result in (according to Murphy's Law) machinegun surprisingly runs dry when you list want it to stop!      

Complexity of the gun
Unlike most magazines which have the mechanism to constantly drive rounds to chambering position, belts needs to be drag into the gun by the gun itself.
Usually a moving cam on the feeding tray cover moves and pushes-pulls the belt to chambering position. The additional parts adding to gun complexity - lowering reliability, increasing gun weight & price etc.

Longer reloading time
As any video game warrior will know, reloading new belt to the gun is far slower than pulling empty mag and inserting new one. This leaves you and your team lacking the suppressive fire, and during the reloading, enemy troops could be using this time to close in on your position. More on the reloading is in the Loading process section.


Handling & guiding the dangling belt(s)
The belt usually requires some sort of guiding from the box to the gun either by the shooter or someone of the machinegun crew members. If the belt is from Non-disintegrating type the operator/s need to handle with two belts from both sides of the gun. How ever, there is the possibility of an "Loose gun"
Most machine guns fires from 'open bolt' so there is a danger of wear-off of the trigger unit result in a gun continue to fire even after a trigger been released. Pop quiz, hotshot: when the gun is magazine fed the shooter simply remove the mag, but when it with belt fed gun, what do U do? Read the Dealing with loose machinegun section to find out!

Belting types




















Non-disintegrating belts
The earliest belt feds were fed using non-disintegrating belts where rounds 'sits' on a belt that enter the gun with cartridges and leave from the other side empty. The belt itself doesn't break to links by the gun mechanism. The empty casing usually eject from different ejecting port from where the belt is leaving. The non-disintegrating belts are more reliable but reducing the gun maneuverability.
The non-disintegrating belts are for multi time use and new cartridges can be placed inside the empty belt after the battle.There are two sub-types of non-disintegrating belts: a single flexible strip made from canvas and belt made from metallic links connected to each other.
These can be seen in use during the first and second world wars. There two types of metallic non-disintegrating belts: Close loop belt and Open loop belt. In close loop belts, the cartridges are held by a ring-like links and the close loop belt have the advantage is that the belt itself is more durable. However, the disadvantage of the close loop belt is the gun can only chamber the rounds using the pull & push method. Open loop belt has cartridges are held by hook like grips and they have the advantage that the machine gun can chamber the rounds using the push-through method.While the disadvantage is that the belt is weaker than the close loop type.

Disintegrating belts
The most common belts type now days are the disintegrated one. Every link in the belt hold two sequential rounds and the links are designed such that previous & later links could hold those rounds as well. A machine gun fed from disintegrating belt will eject empty casing and single links, usually from two separate ejecting ports/windows. Disintegrating belts guns are easier to carry and charge with but the dangers of jamming or link breaking are higher. There are two types of links of disintegrating belts: The close loop link and the open loop link. The close loop link has both cartridges held by the one link are grabbed inside a full loop. This has the advantage is that the belt is overall more durable, but the disadvantage is the gun can only chamber the rounds using the pull & push method (the LSAT LMG is probably the only exception to that rule). The open loop link has cartridges are held by hook like grips. The open loop link has advantage is the gun can chamber the rounds using the push-through method. While the disadvantage is that the belt is weaker than the close loop type.


Linkless feed belt
Also called conveyor belt feed, this is a closed loop non-disintegrating belt. Unlike the two previous types this belt served more as transmission belt than a storage device, such belt is common in aircrafts, gunships, remotely control turrets etc. where the belt drive rounds from some automatic system that reloads fresh rounds to the belt and carry them to the gun to be fired.














The Mystery Belt of LMG11

During the 80's H&K develop a family of weapons around the concept of caseless ammunition. One of those guns was the LMG11 Light Machine-Gun.The gun housed enigmatic loading system, inside the gun stock lays a rectangular cassette of 300 rounds; the rounds are perpendicular to the barrel; some unknown loading system is able to move the rounds from the cassette rotates them 90 degrees and chamber them to 3 rounds' rotating chamber. There is little know about this loading system and how can it accomplish such complicate task. Some sources claim that H&K never proceed beyond mock-up model; other claim there was a belt mechanism of some sort.I have tried to figure it out but so far I can't understand how this thing worked (if it did), The rounds numbering in the cassette do not resemble belt arrangement…So far the best explaining to how this think could work I found in H&K Pro website: "The Cartridges chamber themselves for the glory of the Fatherland!"

Chambering methods

Push-through
The simplest method of chambering is pushing forward the cartridge from the belt into the barrel. Only cartridges with rebated rims could be chambered this way because rimmed cartridge can't slide forward thru the links due to their rims. When using push-through method the belt links can only be open loop type.


\Pull & Push
When rimmed cartridges are involved the machinegun loads the rounds with two-stage method: the bolt backward pull cartridge from the belt then chambering the round to the barrel while moving forward. When using Pull & Push method the belt links can be open or close loop type.



Hybrid
Guns like the Minigun 134 have more complex loading, different from the two previous methods. The cartridges aren't strip out of the belt directly to the barrels but thorough system of what can best be described as an array of rotating rammers & bolts.  



Loading process
When it comes to loading or reloading belt fed gun those guns sucks compares to the loading process of the magazine fed. Generally speaking there are two different loading processes, one for push-through the other to pull & push. Since most of the belt feds firing from open bolt the loading explaining will refer to those guns.

Push-through
This loading process is generally simpler than the push & pull.

  • The operator retracts the charging handle and the bolt moves backward and held by the  trigger unit.
  • The operator opens the feed tray cover, pull belt out of the box, place the first cartridges at the tray and close the tray.
  •  The gun is ready to fire.
Pull & Push
Pull & push (also known as two-stage loading) requires longer loading time.

  • The operator retracts the charging handle and the bolt moves backward and held by the  trigger unit.
  • The operator opens the feed tray cover, pull belt out of the box, place the first cartridges at the tray and close the tray.
  • The operator pull the trigger and the bolt return to forward position.
  • The operator retracts the charging handle again, the bolt strapping round from the belt which the gun mechanism aligns with the barrel.
  • The gun is ready to fire.
Starter tab – Shorting the reloading time
For simplify the loading process some belts equipped with a starter tab in the beginning of the belt. Instead of opening the feeding tray and carefully place the belt before closing the tray the operator push the tab through the feeding window till the tab emerge from the ejection side, and then pull the tab, placing the first round in the chambering position.  






Dual Feeding

Belt & Magazine
When asked "what you prefer, magazine fed or belt fed?" The correct answer should be BOTH! Several light machineguns were designed with both belt tray & magazine housing.
In the realm of LMG it is common to find such guns with the ability to be fed from both magazine and belt. The magazine can be pan, drum or box magazine.Nowadays, modern SAW like FM Minimi & IWI Negev are a prime example of this type of LMG that doesn't require any field conversion and replacing ammo belt with magazine and vice-versa is few seconds long.
Unfortunately, to date there are now LMG with 'feed mode selector'; either the magazine sleeve is empty of magazine or the belt feed tray is empty. Trying to place both types simultaneously will jam the gun. In order to avoid that jam the FM Minimi was designed with magazine housing at 45 degrees, and with the combination of the dust cover mechanically prevents the possibility of simultaneous dual feed. The IWI Negev don't have such mechanism because the magazine house pointing downward. On the positive side with a magazine the gun perform like regular carbine. An open bolt rapid fire carbine that is…
https://www.youtube.com/watch?v=vf52Mznaua0    

Two belts
On the other side of the hill there are the heavy machineguns; several of those models, particularly those that been designed for mounted as a twin gun for naval or anti-air purpose, have the ability to be belt fed from both sides.Those guns, like the M2 Browning, are mounted in pairs one beside the other and need to be fed from different directions. Instead of manufacture two models of the same gun, each a mirror image of the other, those guns can be field converted to been fed from right or left according to the need. Empty cases and links fall through bottom ejection port.Taking the concept of dual belt feeding further are the experimental Belgian FN BRG-15 and the in-service Singaporean CIS 50. Those guns have 'feed mode selector' and with two belts placed in the feed tray simultaneous from both sides. With a switch of a bottom the gun change the loading side and the belt used. The ability to be fed from both sides allows two things: Double the gun ammo capacity, when one ammo box dried out the gunner switch to the reserve box. Flexibility dealing different threats, one belt could be regular cartridges while the other armor-piercing bullets or incendiary bullets.
   
Belt & Electric battery
As we all know – nothing in life is free, and what true to dishwasher electric bill is true to gun automatic cycle. Pushing massive bolt & bolt carrier against compression spring and friction require energy. In regular machinegun the chemical energy of the burning propellant that drives the bullet down the barrel also cycles the gun and its feeding mechanism.
As stated, noting is free, the energy the gun use for cycling is taken out of the muzzle energy the bullet could have. As the gun fire rate increases so is the fraction of propellant energy taken to operate the gun. With miniguns and their rotating multi-barrel structure the demand for energy increase even more. To avoid this problem the more rapid fire guns using external power source, almost always to gun is power from electric source and cycled using electric motor.
Giving that all of those externally powered guns (miniguns & chainguns) are mounted on vehicles the likely power source is the vehicle's alternator or its auxiliary generator.    

One belt & two barrels
Gryazev-Shipunov GSH-23 is the most beautiful ugly unicorn of the machineguns world!
This one of kind soviet auto-cannon is mounted on jetfighters and gunship helicopters and constructs of twin barrel. The gun fed from a single belt and the gun's two bolts cycles and chamber rounds from position no. 1 & 2 on the belt before the gun lever drag the belt two places forward. The gun use alternate fire and have crossed gas system, each fire cycles the other bolt. The result is a gun well balance, when one bolt moves forward the other move backward and vice versa. Having a balanced gun reduce the vibrations and reduce gun wear-off and the danger of fatigue can cause to the aircraft structure.

Dealing with "Loose" Machine Gun
Most belt fed guns fires from open bolt so there's a danger the gun will run wild even if the trigger isn't pulled. When dealing with loose belt fed the operator can’t simple retract the charging handle to restrain the bolt movement or open the feed tray cover, the only answer is to 'starve' to gun, denied it from its ammo.
There are three methods for cut the food supply:
  • Tear the belt
  • This method is more useful for disintegrating belts, the operator saber the belt manually.

Fold the Belt

The belt feds are designed to draw their belts in a straight line, from the belt box to the gun, the operator can fold the belt to opposite side above the close feed tray cover to choke the feeding.














Stab the belt with screwdriver!
Tactical Screwdriver
Machine gun operators sometimes carry a small screwdriver in their one of the pockets.These screwdriver usually used in the process of dismantle and clean the gun. In the case of a loose gun the screwdriver can be pushed to the belt between two rounds and when the gun pulls the belt in the screwdriver will block it. As a testament to this unique method, SEAL Team 6 LMG Operator Neil Roberts, who was killed during the March 2002 Battle of Takur Ghar, wore a screw driver on this tactical gear to service his SAW LMG.



Flexible Feed Chute
Also known as Ammo Feed Chute or Flex Chute this device act as the sleeve of work shirt protects your arms from the surroundings.The Flexible Feed Chute is usually made from metallic links unclosing the ammo belt from most or all direction; some of the designs include softer cover material around the chute to avoid sand & dirt entering the chute. The chute supposed to achieve the following:





  •  Protect the belt from elements that can saber it or carried with the belt into the gun.
  • Though flexible, the chute more rigid than the belt. The chute keeps the belt won't bend or twist too far.
  • The chute stronger than the belt and can stands more bending and pulling forces then the belt can
The problem with Flexible Feed Chute is that of double edge sword, while the chute reduces the chances of failure in the belt it also reduces the ability of the operator to fix the failure if it accrues. The operator may not even able to detect where the jamming or disconnecting of the belt is and even if finding is possible, fixing it will be a pain in the ass.It worth to note that while the tactics needed to stop a loose belt fed gun relays basically on initiated belt jamming it could be nearly impossible to do so with a good feed chute since belt jamming is what the chute is to prevent…    

Tracers' Ratio
Aiming machine guns not always requires sights, one method of aiming is simply fires at the target general directions and observes where the bullets hits by the dust clouds or water sparks of their impact, and then simply correct right/left/up/down the gun accordingly.
Such a backup loop isn't always possible; and firing at night or against aerial targets there aren't clear visible indicators for firing correctness.To solve to problems there are the tracers, tracers are cartridges with bullets fill with illuminate compound. When fired the bullets leave a glowing trail enabling the shooter to correct is aiming. Since tracers have lower ballistic properties and more expensive than regular cartridges most militaries don't use all tracers belts. Most tracers' belts consist of one tracer to several regular. The common ratio is the "1 to 4 ratio" meaning one tracer to four regulars.

Ammo belt box sizes
The different types of belt boxes can be categorized to three groups depend on the place the box is rest/mount while the gun is firing:

Assault box
The smallest and lightest type is the assault box, mounted directly under the machinegun and carry with it. The box usually contains small number of rounds and is latch to gun in a similar way a magazine is connected to gun. In machine guns like the Negev with its magazine housing the upper side of the assault box is shaped as the upper part of STANG magazine so coupling/decoupling is quick as standard STANG magazine.The material those boxes are made of is usually soft material rather than rigid metal or plastic, the reason- reduce the damage those wide boxes can cause when hitting the soldier's ribs when walking or running. Assault boxes provide the maneuverability of magazine fed gun to a belt fed.

Regular box
The regular belt box is a suitcase shaped box with upper opening and upper handle. Firing is done from while the box is rest on the ground next to the gun. Those boxes have larger rounds capacity than the assault boxes but lack their maneuverability, the gun is basically stationary.When the gun is lying in tripod the ammo box sits inside a 'nest' beside the gun. Same is true about tripod as part of vehicle turret – the turret contains place to put the box next to the gun.    

Backpack
The backpack! It seems to be ultimate solution to all of life problems…Maneuverability of an assault box without the load on the gun and the operator hands and with capacity that dwarf those square regular ammo box, what could go wrong? The idea of this limitless belt box isn't new; the Navy Seals carried a specialized stockless M-60 fed from backpack during raids in Vietnam. That specialized gun developed by China Lake research center and known as "ambush gun". Recently two models been presented & tested by the US Army: Ironman Ammunition Pack System & TYR tactical by Huron™ MICO.
So, what's the problem? Why not equipped every machine gunner with such backpack? The main problem as always is the reliability; ammo belts are vulnerable for jamming & tearing. When those problems happens in the other types of boxes where both gun & box are in front of the gunner it's easier to fix the problem, when to box is on your back... good luck sir! Try to imagine scratching your back, know replace the scratch with delicate manual labor and add to it doing that under fire!

http://www.tyrtactical.com/products/details/backpacks/mico-light-and-heavy-machine-gunners-assault-pack/
https://www.youtube.com/watch?v=_e9AQaDKBC4
http://www.fresh.co.il/vBulletin/t-552862-

Arrangement of rounds in the box
Whether it a disintegrating belts or non-disintegrating belts, those belt needs to be folded inside the box; there two ways to folds the belt:

















Layers
The rectangular ammo box stores their rounds in a layers formation, the single belt is folded back and forward and stacked on itself.











Spiral
The drum like ammo boxes holds the rounds in a spiral path
https://www.youtube.com/watch?v=Ol6q5NRiUPo








\




Current Development and Trends of Ammo Belt

LSAT project
The LSAT (Lightweight Small Arms Technologies) as initiated in 2004 and founded by the U.S. Joint Service Small Arms Program, The goal was to resource and develops new technologies and concepts to reduce weight & volume of both gun and ammo. One of the offspring of the program is the LSAT LMG, developed and manufacture by a group of 8 companies led by AAI Corporation.The LSAT LMG appeared to be regular LMG; belt fed from left side, changeable barrels etc.But when it comes to its ammo and interior there is nothing regular about this sweet eye candy… at all!
There two models of this gun, one for firing telescoped polymer cased rounds (CT) the other fires caseless rounds (CS). Both models are fed from disintegrating belts composed of closed loop polymer links.
The belt loaded to the gun as other regular belt. When the gun cycle the 'bolt' moves forward and push cartridge out of the link into a swinging firing chamber, then the firing chamber swing from chambering position to firing position aligning the chamber with the barrel and the gun is ready to fire. When the next cycle repeat the firing chamber swing back to chambering position and the 'bolt' pushes fresh cartridge to the chamber that push the spent cartridge (in the case of CT) or misfire cartridge (in the case of CS) out of the chamber and into front ejection port.
The links are ejected from other ejection port. A short charging handle on the right side of the gun connect to a rammer enable to eject the last round from the chamber after all belt rounds been fired. This irregular chambering system remained me very much the G11 operation… and for no coincidence. Like the G11 the LSAT LMG has to load fragile caseless rounds in simple forward movement without any longitudinal movements or shocks, like G11 it need the ability to clear the chamber out of fragments or unburned propellant. So the unfixed firing chamber concept is used with both guns.The LSAT LMG reached its goals of reducing weight & volume and appears will be the founding father of the next generation of machine guns in years to come.
https://www.youtube.com/watch?v=WlM8IHij6Hs

The Future of Ammo Belts
Other then the LSAT program there is little known about any promising next-gen technologies for the old ammo belt. Not too helpful are the SF movies and computer games, even when belt fed gun is not poorly portrayed the result on screen isn't very imaginary or intriguing. This section, "the future of", will be mostly speculative on my behalf.  

The Near Future:

Combustible strip ammunition belt

The LSAT LMG program is the clear induction of the way to come, and while the LSAT's cartridges are caseless their belt's links aren't.A fully 'caseless' belt will have combustible strip embedded inside the caseless round's propellant along the longitudinal axis of each round.The gun's bolt or bolt carrier will have some sort of "box cutter" to saber the belt and separate leading round from the belt before chamber it to firing chamber. The ignition of the propellant will consume the strip inside of the round.
http://www.google.com/patents/US3696705









Integral ammo box and batter
With the introduction of better and lighter electric batteries and electric motors in the following decades the option of placing chainguns in the hands of infantry will become plausible, not to mention extremely cool! Like their modern cosines, the handheld ones will be fed by both belt and external battery. For simplicity in reloading and supplying those two elements will be integrated in to one unit – an ammo box with a built in battery (boxttery??). With assault box the electric connectors of the box and gun are mated by simply plugging the box into the gun.With the bigger box types there be an extended cord pulled from the box to the gun's connector, like the belt is pulled out of the box into the gun. If the box has Flexible Feed Chute the cord will be integrated within the chute. Other than cycle the gun, the battery can power electric ignition for caseless rounds (ALIENS M56 smart gun?) or optics and such…  

Double-barrel machinegun
The concept of alternate fire machinegun like the Gryazev-Shipunov GSH-23 is something that may one day could been scale down to a handheld version.Currently several of the next-gen AK-like guns developed in Russia have a counter mass that moves opposite the bolt when gun is firing. This agreement results in balanced assault rifle which is very controllable under auto fire. A scale down GSH-23 will give machine gunner controllable rapid rate of fire.



The Far Future:

Belt of disposable power cells or Gauss/Railgun/Plasma bullets or cartridges
In my previous article 'The Magazine' I explore the different types of far future magazines.
The future ammunition may come as some type of discrete units: disposable one-shot power cell, Gaussgun slugs, ampoules of hydrogen slush or something else we can't even guess. Such discrete units can be stacked inside a magazine, and they can also chain to each other in a belt. In such scenario it is stand to reason that the 'rifles' will be fed from magazines loaded with that future ammo while the LMGs feds from belts of the same ammo type.

Integral ammo box with battery
Similar to the boxttery powering the chainguns, the far future boxtteries will power the rail/gauss/plasma guns. The boxttery will contain belt of slugs for railgun/gaussgun or belt of pellets/ampoules for plasma LMG and the battery will powered the firing mechanism.  











Gauss magnetic belt
One neat feature of Gauss slugs is their ability to chain to each other without any belt!
Gauss slugs are simply magnetic cylinders, if those slugs made to be pointy from both sides than those slugs could attach by magnetic attraction to form a belt. The slugs are chained with alternate polarity where one slug's north pole is attach to next slug's south pole - so the Gaussgun need to switch polarity every shot to throw the slug down the barrel and not to the shooter shoulder! Needless to say, a great consideration will need to thought-out of how to prevent different layers of the belt in the ammo box to stick to one another.  

Science Fiction and the Ammo Belts
In popular media in general and science fiction in particular,  ammo belts and belt-fed guns share the same fate of their younger sibling – the magazine; in the golden age of science fiction, the weapon of choice for any author or movie writer was a silverfish ray-gun with bottomless battery, no misfeeding or misfiring, no moving parts spewing empty cases and links etc. In recent 30 years the trend toward slugs' throwers (cough! ALIENS, cough) return the magazines to the scene. Though the portraying of magazines was far than perfect it still much better than the portraying of the belt feds. A few examples in recent years give me hope that not all is lost. The most promising arena is the first person shooter games, when the games deals with real gun –shooting, choking & reloading are portrays with great accuracy.

Examples:

Hydra Disposable Power Cells Belt Backpack from Captain America: the First Avenger 
Although cheesy and soft SF - the first Captain America movie features very unique ammo belt design. All Hydra weapons powered using bluish energy extracted from the Tesseract and stored as small blue orbs. The heavier elements of Hydra troopers carry gun firing this denigrating blue bolt, those guns are fed from backpack thru a flexible feed chute what lead me to believe that those orbs are carried by some sort of a belt from the pack to the gun. Supporting my thesis are small blue lights glittering thru the links of the chute 'indicating' that there orbs there on their path between the pack and the gun. No empty belt or links are leaving the gun so I guess Hydra's engineers must design the gun such that some of the denigrating energy used to denigrate the belt itself, nicely done lads…  

Old Painless Ammo Belt Backpack from Predator
What would Predator be without the beloved Old painless? And what would Old painless be without is trusty companion, Old Back pain?? This M134 is been fed from ammo backpack thru a flexible feed chute. The pack holds approximately 550 rounds of 7.62x51mm NATO. Ol' painless most likely not be the first to present the backpack & flexible feed chute concept on the silver screen but for sure it the most memorable and loved appearance! In the more correct sequel Predators from 2010, there is another handheld rotary cannon fed from an ammo belt backpack as a nod to the original film.

The APU Automatic Reloading System and Ammo Trolleys from the Matrix Revolution 
While Neo fight his battle against Agent Smith inside the Matrix, back in reality, the fight for the survival of Zion rest on the metallic shoulders of the Armored Personnel Unit warriors. The APU holds two auto cannons in their "hands" which feeds from two ammo boxes placed on the unit "back". Reloading the units while fighting is the job of Zion's "power monkeys" – a group of men/boys carry those duty during the apex of combat is to transport ammo boxes from the sheltered ammo room to the APU in-field using a specialized trolleys. The trolleys have uplifting ramps to move the boxes from floor height to the APU's "back". During the Battle of the Docks, Kid was a member of the Power Monkeys that delivered fresh boxes of ammo to APUs during the choas of the bloody battle. This was all seen on-screen.
https://www.youtube.com/watch?v=_MtlllCQ0AU

The CARB Weapon System LMG11 type belt feeding from AVATAR
This movie is set at the year 2154 so I guess H&K did unlock the secrets around the LMG11 belt. When raiding the Navi the RDA uses the CARB assault rifle, this gun carries a box-like magazine in a bullpup configuration.Thing is the box dimensions are all wrong, the gun's caseless round is 6.2x35mm and the box is very long and wider than 35mm, plus the box contains 80 rounds.Giving all stated above I think there are compelling evidences that those rounds are perpendicular to the barrel and they been fed similar to the ancient LMG11 (in the 22th century the 80's of the 20th probably viewed as some dark ages…).

The LSAT LMG from Call of Duty:  Black ops 2 & Ghosts
The  caseless LSAT light machine guns famously appears in both Call of Duty Black Ops II & Ghosts with a great deal of accuracy to the real-world weapon. In Black Ops 2 the gun have rounds digital counter which don't appears in the real gun. Not only is this a rare appearance of an caseless weapon, but a belt-fed light machine gun to boot!




The XO-16 40mm Automatic Loading System from Titanfall
In the computer game Titanfall, huge humanoid Mechas carries huge guns with their mechanic palms. Two of those guns are the auto cannons XO-16 & 40mm, and while replacing the empty ammo box with new one been done using the Titan left "arm", pulling the belt from the box into the gun isn't done by the 'arm' cause it too clumsy but as part of the guns inborn mechanism.

https://www.youtube.com/watch?v=iQxxcDyCoU0

The M56 Smartgun drum of non-disintegrating ammo belt from ALIENS
During the firing spree in atmosphere processor scene privates Vasquez & Drake spray & pray using the M56 smartgun. The gun is a dressed-up German MG42 machine gun, the MG42 is a belt fed from a saddle drum, and the belt is non-disintegrating arrange in a spiral path in the drum. A closer look in the atmosphere processor scene revealed the empty belt emerge from the gun right side while the empty casing been digitally removed from the video like the M41A1 pulse rifle so both could appear caseless guns.  

Next on FWS Armory...a Song of Fire and Water
For my next FWS Armory I leave it to you, the trusty FWS readers, to decide which will be my next article. In the Yellow corner is the flamethrower article all blazing and in the Blue corner it’s the underwater firearms article feeling a bit blue. Which of them you like to see and read? Leave a comment and tell me!







Next Time on FWS...
There are times when a book takes the central ideas about military sci-fi and alters them. Author Chris Martin and artist Ben Mauro have unleashed such a novel with Engines of Extinction: Episode I "The End and the The Means". In the next installment of the FWS serial on book reviews, we will be diving into the shadowy world of Engines of Extinction.

7 comments:

  1. I was always wondered how does the belt feed works, thank you for explaining! Great article, you covered every aspect of this feeding method! With that HK machine gun, is it possible that there was no belt, and it was just more mock-up than working system? I hope not ;)
    And i prefer blogpost about flamethrowers than underwater weapons, mostly because of Aliens, it's my vote :3

    ReplyDelete
  2. I vote flamethrowers!

    ReplyDelete
    Replies
    1. Agreed, would love to see an article about the flammenwerfer. Sucks that we can't use them in the u.s.army but I definitely understand why. Shit burnt bodies already creap me out so just imagine actually doing it... Uhhhh

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  3. Nice article Yoel, as usual.

    I too have stared at the HK LMG11 for hours trying to figure out how that damn thing worked, and never could figure it out. Finally I just gave up on reverse engineering from a few old pictures and came up with my own system for a caseless LMG. What I wound up with used a plastic magazine with no spring and a mechanically indexed ratcheting "feed tower" that was integral to the gun. The magazines would be issued like stripper clips: use up the ammo, and throw them away. I designed two different weapons using this system, an assault rifle and a squad automatic weapon. The assault rifle would simply be loaded with one magazine in a bullpup layout, with a standard 30 round capacity. The SAW on the other hand could be loaded with four of these magazines for a grand total of 120 rounds. It fed from one magazine until it was used up and then a mechanism ejects the magazine like an M1 Garand, and then a new magazine is pushed into place automatically. This could also potentially be reloaded while the weapon is firing, adding in extra magazines as the ammunition is depleted, and it would allow SAW gunners to freely exchange ammo with riflemen of necessary. The downside to this system is obviously weight and mechanical complexity. The extra weight on the gun due to the complex feeding process would likely be offset by the lighter weight of magazines and ammunition, but it's mechanical complexity would likely hamper it's in field performance and reliability.

    The issue I have with mechanical complexity stems from real world guns, and has killed all of my optimism for the LSAT program. Too complex, and the caseless ammo version will most likely suck. It will overheat faster, probably wear out faster, be fed from delicate ammunition and is just too mechanically complex. Polymer cased telescoped ammo with tried and true reverse extraction is what I endorse. A wider extractor claw and fluted chamber would likely allow the gun to extract just as reliably as any modern metallic cartridge system, or perhaps even moreso, and the weight and space savings from polymer cased telescoped ammunition is almost as good as caseless. Plus the case seals the chamber, enhances durability of the ammo, and helps shed waste heat.

    As far as your next article, I did some research myself on underwater firearms just last week, and there's really not a whole lot of content there, just some odd Russian designs, one from Heckler & Koch (of course) and some modern developments using supercavitating projectiles. Flamethrowers on the other hand have been in use in one form or another for centuries, so I vote flamethrowers.

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    1. I know what you're talking about regards the LMG 11! As Leon from Blade Runner said –" Nothing is worse than having an itch you can never scratch! "
      About your caseless weapon system you designed, is it a thought experiment or more?
      Consider that any springless magazine with "feed tower" will probably have to be totally enclosed inside the gun like the M1 eight rounds en-block clip is. Eight rounds clip is small but 30 rounds magazine will require bulky gun to hold this magazine inside.
      Another issue is that such weapon system could only use 30r mags. Regular guns can use mags in different lengths, from 5 to 30.
      With the SAW – are the four mags stacked side by side or one after the other?
      And now to the LSAT LMG – I totally disagree! The only additional component in the LSAT that regular LMG don’t have is the swinging firing chamber, not very complicate part.
      On the other hand the LSAT bolt doesn't have extractor or ejector tooth and those are critical components. In terms of reliability, replacing extractor & ejector tooth with swinging firing chamber is a good deal.
      Reveres extraction with polymer cartridges is problematic, adding extractor tooth to bolt requires bolt's diameter larger than the cartridge's diameter. That means that the bolt couldn't pass throw the full loop links since the loop's inner diameter is equal to the cartridge's diameter.
      If you change the chambering method to pull & push/two-stage chambering the cartridges will required to have external rims.
      If you keep the push chambering the links need to open loop, reducing the structure strength and force to return to metallic links.
      Thanks for reading and commenting!
      Yoel

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    2. My design is mostly for my own science fiction meanderings, but I have drawn out the mechanical workings in detail. It's not particularly bulky, the magazine housing hangs down only slightly lower than the pistol grip, and it is actually slightly shorter than a 30-round ar-15 magazine since it doesn't have to accommodate a spring. I don't think the weapon using only 30 round magazines is a big issue, since thats what is used 99% of time in modern weapons, but the way the feed system is designed you could actually load reduced capacity magazines if you felt the need. Higher capacities than 30 would be tricky, however, but that's what the SAW is for. I designed the SAW with both back to back and side by side layouts, and the side by side is if I remember correctly what I chose for the final design, but I'd have to find the old drawings to be sure. By the way, the action doesn't have to be opened to load it. You simply insert the magazine into the well like you would an AR or similar weapon, which is why the mechanically ratcheting feed tower (that's what I call it) is necessary. This mechanism does add to the mechanical complexity, but since magazine issues are the number one source of stoppages in modern weapons there might be a net increase in reliability, but the only way to know for sure is to build and test it.

      I may just be a pessimist, but to me the added components of the swinging chamber and use of some kind of a rammer to chamber the rounds just seems unnecessary. That means that instead of just having a bolt reciprocating back and forth, you have to have some kind of an operating rod, rammer, and some kind of a linkage to swing the chamber back and forth, which requires who knows how many extra parts, likely with critical operating tolerances. So it has more components that can fail, and more cracks and crevices for dirt to gum up the action. There's also the possibility of components locking up: anybody who's run a lever action very much will know what I'm talking about here, with extra components sliding past each other sometimes things just stop working and seize up. Maybe I'm wrong, but we'll never know for sure until field trials, and simple firearms have always outperformed complex ones in real world conditions (assuming both are well-made, I've heard lots of horror stories about cheap AK's).

      The polymer cased rounds I advocate using could be fed almost like any metallic cartridge, so they really wouldn't be very different in function to existing weapons that are proven to work. They may even work better, casings may prove less likely to stick to the chamber upon firing. It sounds counter-intuitive, but metals behave strangely when subject to high pressures, and many steel cased rounds are already coated with polymers to lubricate the case to enhance extraction.

      I doubt I'm wrong about the caseless version though. Caseless ammo is cool in theory but in practice has never worked well. The cartridge casing just performs too many roles to be easily replaced. Plus since the LSAT is a machine gun the caseless version will overheat like hell.

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  4. From what I understand, most LMGs are either not including, or removing the ability to use standard box magazines with the LMGs. It is more of a nice to have gimmicky feature that was never used in the real world and simply added unneeded weight to the gun.

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