Bullpup vs. classic rifle designs?

[A Can of Man]

M-16's not very lefty-friendly either - no side-ejecting rifle is going to be very friendly to left-handed shooters, even with a case deflector. Which bullpup rifles eject downward?

Actually I don't see the big deal about the side ejection. It ejects far forward enough not to hit me in the face or anything. Yes I shoot left handed.

 

[CanadianCombat]

I can't stand the look of bullpup rifles. I guess I'm just used to seeing and using AR-15 type rifles, and I won't be changing my ways anytime soon.

 

[5.56X45mm]

Until the 40 Watt Phased Plasma Rifle or Lightsaber comes out we're stuck....

The next major evolution in firearms will not be the layout of the rifle. It will be the ammunition. We all talk about cutting edge and ahead of it's time...

The Germans take the cake with the Heckler & Koch G11. Caseless ammunition. It saves weight and completely changes the playing field for you soldier. He can carry far more ammo for less weight.

This rifle was going to be the standard rifle of the West German Army but the Cold War ended, the DDR became no more, and the German State just became broke. So it was scrapped and the G36 (H&K backup design) was approved and issued because of the price of ammo. There were already billions of rounds of 5.56x45mm floating around Europe because of NATO and the USA. The idea of stocking up on billions of 4.73x33mm Caseless rounds was an expensive project.



Right now the USA is looking into LSAT (Lightweight Small Arms Technologies). It's a caseless 5.56x45mm system. They have two designs. A 100% complete caseless system and a stopgap design. Plastic cased-telescoped ammo.

Large Image file
http://www.defensereview.com/stories/ausawintersymposium2007/AAI LSAT_4/DSC02547.JPG

The Cased Telescoped (CT) ammunition (above) is one of the approaches to meeting LSAT’s weight reduction goals. The most current generation, “Spiral 2” CT, uses specialized polymer formulations for the cartridge case and end cap, but priming is conventional. Six-hundred rounds of 5.56 CT weighs 35 percent less than an equal number of 5.56x45 mm rounds.

National Rifleman, National Rifle Association
http://www.nrapublications.org/tar/LSAT.asp

The Caseless Telescoped (CL) cartridges (top), developed by Alliant TechSystems, use the propellant itself for the role of the “case,” which is fully consumed on firing.
National Rifleman, National Rifle Association
http://www.nrapublications.org/tar/LSAT.asp

The Lightweight Small Arms Technologies program (LSAT) has been on our radar screen since its inception in 2003. Plastic-cased cartridges are already performing well, and caseless ammunition—a concept dating back to the dawn of firearms—is said to offer the greatest potential. Today, these high-tech cartridges and the innovative lightweight small arms that fire them are showing great promise. What emerges from these experiments is likely to yield benefits not only to the military, but also to law enforcement and to the shooting sports.

It’s real and right now: a dramatically different squad automatic weapon (SAW) that fires radically new ammunition. And this combination is half the combat weight of the M249, the current SAW. We asked the Army’s program manager how soon it could be in the hands of Americas warfighters? That is a tough question, so lets go back a few years.

For further information read the NRA national Rifleman Article.
http://www.nrapublications.org/tar/LSAT.asp

The reason AAI is starting with plastic cased-telescoped ammo is that caseless ammo is a higher-risk proposition involving greater technical and physical challenges than cased telescoped ammo. One of the primary challenges with caseless telescoped ammo (CL ammo) is how to continuously and consistently seal the chamber as the weapon is fired (i.e. provide for a repeatable seal), especially on full-auto under high round count. According to legendary infantry small arms designer (a.k.a. firearms designer a.k.a. gun designer) Jim Sullivan (L. James Sullvian), CEO of small arms development firm Arm West, LLC, "if you can't seal that breach, you've gotta' go back to a muzzle-loading single shot. You have to seal the breach, and you've gotta' seal it with every shot. And, you can't have something that wears out. So, you've gotta' replace the seal with every shot." With cased ammo, the case itself acts as the renewable chamber-sealing device a.k.a. "replaceable seal" [replaceable breach seal], as Sullivan calls it, and a brass case seams to work the best at this. "Cartridge brass is unique stuff", Sullivan says. With caseless ammo (caseless telescoped ammo), you lose this replaceable seal.

Now, a plastic case is better than no case (with regard to providing a fresh breach seal for each shot), of course, but it ain't brass, either. For one thing, plastic, historically, has tended to melt/burn at the high temperatures generated by full-auto weapons (small arms). It's possible that AAI has solved this problem by utilizing some kind of high-tech heat-resistant plastic that can handle these temperatures, but that remains to be seen. Assuming the plastic they're using can handle the high temperatures of full-auto fire at high round count (or even low round count), the plasic case should assist in insulating the chamber so it doesn't heat up to much (unconfirmed/unverified). It's also possible that the LSAT LMG/SAW prototype's swinging/"rotating" chamber reduces the amount of heat transfered to the chamber, and thus to each subsequent plastic case as it's loaded in, but we haven't been able to confirm this, either.

However, this same insulative property keeps the plastic cartridge case from performing another function of a brass cartridge case, and that' removing (i.e. expelling) heat from the weapon upon extraction and ejection. A brass case absorbs heat upon firing the round, and that absorbed heat is immediately removed from the weapon upon extraction and ejection of the case. Plastic doesn't offer this same heat-removal bonus.


Aside from the plastic cartridge casing, it's DefenseReview's understanding that cased telescoped ammo (CT ammo) itself has a few challenges to overcome. According to Sullivan, one of the primary challenges is achieving adequate and consistent projectile velocity, since the round is literally sitting inside the gun powder inside the case. This makes it very difficult to keep enough of the ignited powder (i.e. propellant gases) behind the bullet upon firing/detonation of the cartridge. In other words, you have to prevent too much of the propellant gases (from the burning powder) from escaping around the bullet as it's propelled down the barrel after firing.

The whole reason for going to plastic cased telescoped ammo (plastic CT ammo) and caseless ammo (CL ammo) in the first place is to save weight, i.e. to lighten the infantry warfighter's load, and to perhaps shorten the weapon's action (bolt carrier group's reciprocating distance, for instance) so you can speed up the full-auto-burst time. AAI claims in its LSAT fact sheet that it's achieved an overall weapon/ammo system weight (LSAT prototype weapon plus 600 rounds) of 22.9 lbs (CT ammo system) and 19.1 lbs (CL ammo system). This constitutes a 40-50% weight reduction vs. the FN M249 SAW + 600 rounds of standard 5.56x45mm NATO ammo (38 lbs OA weight). Whether or not AAI can achieve the requisite weapon reliability, accuracy, and lethality (on full-auto at high round count under adverse conditions) required for an infantry combat weapon with plastic CT and CL ammo remains to be seen. Time will tell.

However, what if you could accomplish the specified 35% weight reduction (weapon + 600 rounds), and perhaps even more, while avoiding the incumbent technical and physical challenges of these two ammo technologies (CT and CL)? What if you could cut the weight AND retain all of the advantages of a metallic cartridge case? This will be the subject of a subsequent DefenseReview article on the Arm West "Backbone" Weapon System a.k.a. Backbone Family of Lightweight Machine Guns (including a modular assault rifle/carbine/LMG/SAW) and ammo concepts.



http://www.defensereview.com/modules.php?name=News&file=article&sid=1000

 

[senojekips]

I can't stand the look of bullpup rifles. I guess I'm just used to seeing and using AR-15 type rifles, and I won't be changing my ways anytime soon.

The day when "Looks" become a consideration, will be the day we just give up all development.

Weapons of war are not designed or adopted for their "looks".

 

[The Other Guy]

Weapons of war are not designed or adopted for their "looks".

If weapons were designed for looks, the M-16 and MiG-21 would have never left the drawing board...

 

[senojekips]

Right now the USA is looking into LSAT (Lightweight Small Arms Technologies). It's a caseless 5.56x45mm system. They have two designs. A 100% complete caseless system and a stopgap design. Plastic cased-telescoped ammo.

I'd have to have a much closer lok at this, but what strikes me in this cas is the physical size (bulk) of the ammunition. Any gains in weight reduction would be immediately offset by the fewer number of rounds that you have room to carry. Plus, I couldn't see this type of ammo being suitable for standard type magazines because of it's bulk. Anyway it's only an adaptation of the old "Dardick Tround" and no doubt has many of the same problems.

But I'll wait and see.

 

[c/Commander]

Actually I don't see the big deal about the side ejection. It ejects far forward enough not to hit me in the face or anything. Yes I shoot left handed.

This is true for single shooters, but side ejection has other issues. This is a picture I took of a mid in my Marine Week platoon who unfortunately took a hot casing in the neck from the shooter next to him. This is a worst-case, but obviously not a good thing regardless. Someone needs to design an M-16 variant that ejects to the ground

 

[5.56X45mm]

I'd have to have a much closer lok at this, but what strikes me in this cas is the physical size (bulk) of the ammunition. Any gains in weight reduction would be immediately offset by the fewer number of rounds that you have room to carry. Plus, I couldn't see this type of ammo being suitable for standard type magazines because of it's bulk. Anyway it's only an adaptation of the old "Dardick Tround" and no doubt has many of the same problems.

But I'll wait and see.

Ahhh... the old Dardick Tround. I haven't heard about one of those in years. Anyways...

From the complete article in National Rifleman. The "Lipstick Round" and the Caseless round are about the same size in diameter as the standard 5.56x45mm cartridge. For a magazine feed weapon system. The only one that got off the ground was the G11 and it's system. The LSAT is designed as a possible future replacement of the FN M249 (FN Minimi). Allowing our GIs to carry a SAW that weighs less, performs the same function, and even fires a projectile with the same ballistics as the 5.56x45mm SS109 62Gr FMJ is a pretty good set up.

Of course this is all in the testing stage and who knows about it's sturdiness out in the field with a bunch of GIs that can destroy a block of wood by simply looking at it. If it works and can be made to be Soldier Proof then we have a fine product.

But that is the future. Caseless ammunition is the next major evolution. Every major advancement in the world of firearms came with the evolution of the ammunition first and then with the mechanics of the firearms themselves. Black Powder went from Match Lock, Wheel Lock, Flint Lock, to Percussion Cap. Then it was cased ammunition. The evolution of that was first from rim fire to center fire and then into rimmed, semi-rimmed, to rimless, and the feeding mechanics. Also the evolution from black powdered cased ammunition to smokeless was also the major advancement within the evolution of firearm design because of of advancement of ammunition.

Trust me.... the future is caseless ammo. When? I can't answer that but I believe it will be at some point within my life time.

Crappy photo.... I know but you can somewhat get an idea.

 

[senojekips]

Thanks Luis, that's answered that question, the photo with the two different rounds side by side is much better.

Caseless rounds have been in the pipeline for many years, and I have little problem with the idea that they will figure in our future firearms design, no doubt the boffins are making some headway. Previously there has always been a problem of some sort, not the least of which was deterioration of the propellant and lack of mechanical strength (resistance to breakage and chipping etc). There was also a big worry about ignition from flash in the case of an explosion.

 

[A Can of Man]

This is true for single shooters, but side ejection has other issues. This is a picture I took of a mid in my Marine Week platoon who unfortunately took a hot casing in the neck from the shooter next to him. This is a worst-case, but obviously not a good thing regardless. Someone needs to design an M-16 variant that ejects to the ground

Which is why you should flip up the collar on your flak jacket. At least ours has one.
The issue with downward ejecting cases would be that if you were shooting from some kind of cover, i.e. you have something under your weapon such as a sand bag, hard ground etc., the casing can bounce up back at your face and that will be a surefire way to screw up your day.
The FN P90 has a downward ejecting system but I don't know if there are any real issues with it or not. Then again, it's a real compact PDW so I don't think it's even meant to be fired while prone.

 

[c/Commander]

The collar was flipped up and he was wearing a throat protector; but it doesn't help if the round comes in from the top. Actually it probably caused a worse burn than would otherwise have occured; he couldn't get the damn thing out without taking off his OTV.

 

[A Can of Man]

Call it bad luck then. Like slipping down a flight of stairs. Sh*t happens.

 

[todd8541]

hello guys im new here.

I read all of the posts about the difference from the bullpup and convential style weapon.

Regarding the training, I am sorry that arguement doesnt hold water. Alittle known fact about why the desert storm started so late is the marine corps were still using the M60 tank. The american government waited to additional M1's were produced and the marines were trained on the new tank. So in four months additional tanks had to be produced delivered marines trained and delivered to the combat area by boat.

As far as the M4/M16. I love the architecture (ergonics) but the operating system sucks it jams like crazy. You have to keep it imaculate. Before you claim i was lazy I am a marine scout/sniper(no longer serving) I know the importance of cleaning. I was so adimate about cleaning the weapon I would punch the bore while waiting to fire when we went to the range.

the M16 had several issues with it's introduction during the vietnam war. One Mcnamarra (sp) would not allow the internals of to be chromed even when he was told by the designer that it was necessary to function properly because it cost too much money. Second he felt there wasn't a need for cleaning equipment therefore the military was never issued cleaning equipment. It wasn't until marines and soldiers started writing their congressmen of the issue of the weapons jaming during fire fights causing more men to die.

The bullpup architecture appeals to me more because you have the advantage of a short weapon without sacrificing long rang accuracy. With that being said the lack of ambidextoius (sp) is a concern. Not from the fact of lefties but righties will need to fire left handed too.

All of the accessories can be adapted to either platform. The lack of screws is not a weapon related issues but unit logistics. honestly over 90 percent of that crap is for you xbox combat kids to feel cool. Other than night sights and grenade launcher Id throw the rest of that crap in the trash. The fatigue and increased difficulty in well aimed shots due to the extra wt on the weapon offsets the benefits of the few times you will actualy use it. A well trained marine and soldier doesn't need that crap.

there will never be a perfect weapon. Case ejection will always be a issue one way or another. there's even a weapon that pushes the spent brass thru a tube above the barrel. I am alittle leary about that system but I am digressing. While a ejected brass hurts like hell and can give 2nd degree burns Whine whine so what. if you cant take alittle burn trust me you dont need to be in combat.

All i want is a weapon that is user friendly (ergonomics and architecture), one that will function even though its got alittle trash in it from when I was low crawling or dirt kicked up during high winds, and have repeatable accuracy round from round. It needs to have a minimum of 500 yards of accuracy yet manuevable for CQC.

My perfect weapon would be a M14 operating system in a light weight platform like the M16 in a bullpup configuration and I would buy every time i had a choice. The only down fall with the M14 is it ejects up and to the right. A creative engineer can overcome that and make it usable when firing left or right handed.

ok ill shut up now haha have a merry christmas and new years
Todd

 

[old woody]

Bullpup seems like a good idea.
How does the FN P90 type of magazine feed work? The reloading does look like a b*tch but it does hold more ammo, which you can see through the transparent magazine just by looking down. That might be the next direction for automatic weapons.
Also I too can see the great benefit of having the ammunition CLOSE to your body's center. It'll feel a heck of a lot lighter than having a magazine or two hanging away.

I've never used it but some aspects are obvious. Prone,the top mag is not as in the way. that the forward hand is the trigger means the weapon can be probably fired rather well one hand. In a sudden emergency,if wounded,if hanging from a parachute or dragging some gear or a wounded friend...that might be damn handy.

While the P90 layout is perhaps the future in terms of ergonomics, I'd think the concept begins to look better scaled up a bit. Picture it a bt larger and built for a new 10 mm round that comes in a subsonic for silenced commando/urban use and a more powerful,aerodynamic round with good accuracy to 300 m.

With situations where the soldier may go to battle in a vehicle or chopper,or be air dropped, might fight in dense jungles or in buildings, a compact weapon with a clean line,not a lot of stuff to snag...can be a +.

I would not be looking to re-equip everyone. I'd be more apt to start new troops,or special units, with this if they have a role where it makes sense.
It's been evident that the circumstances of Iraq,Vietnam, Afghanistan are quite a bit different. The M-16,after some early issues, worked well for Nam. In Iraq it was good in the open,but not ideal in an urban fight. In Afghanistan,there's often fights where the enemy is at a distance and small units,so there's been a swing to 7.62 rifles with some sniper qualities. Notably the Stoner design which resembles a sniperized AR 15,has semi auto and 800 m effectiveness.

As missions and wars get more unconventional and deal with a range of environments it seems logical to have gear to fit a range of circumstances.

For a main battle rifle? I think the case at the moment is that the military has to deal with the economics of a big transition. As is, there's stuff that's on hold. I'm guessing the US military currently owns more M-16's than they have infantry to carry them. They COULD equip a brigade with a new bullpup,just to see how that works out. I doubt that short term it gets beyond that. Someday...many of the existing M-16's will have enough accumulated wear and tear that the Army/Marines might do the next rifle on a full scale...and I'd think that next rifle is probably a bullpup

 

[Spartan613]

Put simply, retains the same barrel length (with all the advantages of that) in a shorter, and better balanced package. They're just as simple to use as a conventional layout after training. I cut my teeth on the L1A1 SLR and M16A1 and converted to the F88 (Steyr AUG) with no problem. I can switch between the F88 and MP5 and M4 with no difficulties.

 

[Warwick]

Same here Spartan, though I don't have an MP5 qual.
Got over the initial ergonomics change with the F88 after constant use.
Seems some people just can't give up their long arms!

 

[GHR]

I think that the bullpup has too many disadvantages. Bullpup designs are mechanically more complex, requiring a long trigger linkage, and control system linkages. This seriously degrades both control feel, and reliability, and increases bulk and weight and if a bullpup has a catastrophic failure, instead of the explosion being six or 8 inches in front of your eyes, its right at your eye socket, or touching your cheekbone or ear. The only good thing is if the bolt fly’s back, it doesn't end up in your eye socket. They also tend to eject hot brass, and vent hot gasses in the vicinity of your eyes and ears

Mag changes on a bullpup are much slower because they require more repositioning, and are difficult to see without fully dismounting the rifle. A conventional rifle allows you to see your mag changes, and is more easily maneuvered with your dominant hand, which makes mag changes easier in general. More importantly a human being can naturally bring their hands together in the dark. Magazine wells should always be either in your dominant hand, or just in front of it, because it is far more difficult to manipulate anything dexterously that is located behind your dominant hand. Because of the positioning of the mag, bullpups can be difficult, or impossible to fire while prone also the magazine is by far the lowest point of the rifle; and being located behind the dominant hand, it will tend to strike the ground forcing the muzzle downward. This also causes problems with mags being warped or ripped out of the magwell, or the rifle itself being ripped out of the users hand when hitting the deck; that a conventional rifle doesn't have (the muzzle will just bounce up)

Charging the rifle and manipulating the operating handle is often more difficult, and sometimes can't be done without dismounting the rifle, or reaching over with your support hand.Bullpups are naturally balanced in a non-instinctive way; the balance point on most bullpups is in between your hand and your shoulder when mounted. The only way to correct this is to put heavy things in front of your dominant hand, or to make the weapon short and light enough that this won't make a difference (and even then it will still be more awkward and less instinctive to point). This will tend to make a bullpup shift unless it is tightly mounted to your shoulder, and especially will tend to shift during rapid fire. This tendency is somewhat countered by the position of your support hand so far forward on the barrel, but not sufficiently so. A conventional rifle is balanced in between your dominant and support hands; and there are good reasons for that. A human being naturally handles things better that balance in the palm, or in front of it.

A lot of this can be worked around with training, but what it comes down to is that the only good thing about a bullpup is the short overall length in relation to their barrel length; and that is not advantage enough to outweigh the disadvantages for most missions.

 

[MC Martel]

I find the argument that the ergonomics of the bullpup design are inherently worse to not hold much water, especially with the IMI Tavor, which,from what I gather, has been designed while integrating significant erganomic knowledge, something I tend to trust the Israeli's to be good at.
Secondly, the current round in us in the US military, the 5.56x45 NATO round, actually has excellent terminal ballistics, but only when terminal velocity is high enough to fragment (I've heard 2700 FPS quoted as the required terminal velocity, for the M855 bullet, but don't quote me on that). The velocity of the round is highly dependent on the length of the gun, and with the current trend towards shorter weapons like the M4, the loss of those extra few inches of barrel can seriously impact the range at which the round has effective terminal ballistics, and I don't think you can underestimate how important that is.

(After some digging I found an excellent article that explains the wounding mechanism very well with pictures and the importance of barrel length/velocity on that, http://ammo.ar15.com/ammo/ take a look at this)

 

[ryancb]

I'd have to agree with the Ensign on this senario. I've deployed to both Iraq and Afghanistan and our mission was just that. OUR MISSION. If we were distracted with, things going on at home, or new training, or a KIA in the unit, ECT ECT... our moral went right out the window. Ofcourse as men (some women) in the military, we love guns. But we all new it was going to be a pain in the *** if we had to train on a new rifle platform. Some of us got that chance and carried AK's but thats no big deal seeing as how we all had 308's back home. So in conclusion i'd again like to thank the navy Ensign for bringing up that subject. It is and would be a very big distraction to train soldiers on brand new weapon systems while serving durring a war time period. That could actually cost millions + young men and women their lives.

 

[Trooper1854]

I remember the transition from L1a1 SLR to SA-80. I was part of the training team for the new weapon in my unit.
Oh lord! People were threatening to leave the forces and all kind of things. One CSM refused point blank to have anything to do with it!(He had an attitude adjustment from the RSM!)
As has been said, same barrel length, but more compact.
Though slightly heavier, the SA-80 was easier to carry, especially with the new sling system.
I never had problems firing it in the prone position, and I never knew anyone who did.
The only problem we had with it was reliability, but it was a new weapon.
I never used it in anger, so can not personaly comment there, but I know guys who have and they were happy with it.
More ammo, 30 rounds, though initialy we had 20 round box mags.
Accuracy wise, I found little to choose between them.
I think it was mostly a looks issue. Some bullpups are ugly!