Owen
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50% decrease in Life Cycle Cost.
The evolution of fighting rifles
- Thread starter Tirod
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50% decrease in Life Cycle Cost.
Hatterasguy
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0, my point is military budgets are going to be shrinking a lot in the future so unless another big war comes around their will be no further work done to replace the M4 for the foreseeable future. But what do we already have that's a 21st century design? The FN Scar.
As a bean counter its cheaper to use what you already have.
On the operating system angle, I'd offer a counter point to DI: Roller-Delayed blowback. The CETME/G3/MP5 family of guns use them. The soviets even had a prototype weapon using roller-delayed in the 1956 trial for a replacement to the AK-47. This system offers excellent accuracy and controllability, as was found by the Soviet designers. The only thing that needs to touch the barrel is the roller-lockup system, no gas tube, no piston, no nothing. I recall it is not uncommon for G3 rifles to shoot 1.5 MOA or better off the rack. That's quite impressive accuracy.
Additionally, this system seems to have little trouble with fowling of the action. Some posters have mentioned PTR91/HK91's with over a milimeter of caked on carbon in the chamber and action with absolutely no impact on the rifle's function.
One of the common themes with DI guns is they are dirty. I've heard all the arguments that the gas goes into the gas key and into the bolt, but, unless the gas tube and gas key form a air-tight seal that is able to stand up to several tens of thousdands of PSI of pressure, there's going to be blow-by exiting the tube into a receiver. For there to be no blow-by from the imperfect seal would have to violate some laws of fluid mechanics, mainly the whole going from high pressure to low pressure thing.
This inherent dirtiness has been repeatedly demonstrated by shooting 100 rounds through an AR15 and 100 rounds through an AK. When all said and done, the AR15 is ALWAYS dirtier than the AK even when premium ammo is used in the AR and dirty Wolf ammo in the AK.
That said, is the DI system good enough? Yes. It is not a "white glove test" system, and it can tolerate a fair amount of fowling, with the biggest issue in AR reliability being magazines, followed by an over-ambitious bolt design.
Additionally, this system seems to have little trouble with fowling of the action. Some posters have mentioned PTR91/HK91's with over a milimeter of caked on carbon in the chamber and action with absolutely no impact on the rifle's function.
One of the common themes with DI guns is they are dirty. I've heard all the arguments that the gas goes into the gas key and into the bolt, but, unless the gas tube and gas key form a air-tight seal that is able to stand up to several tens of thousdands of PSI of pressure, there's going to be blow-by exiting the tube into a receiver. For there to be no blow-by from the imperfect seal would have to violate some laws of fluid mechanics, mainly the whole going from high pressure to low pressure thing.
This inherent dirtiness has been repeatedly demonstrated by shooting 100 rounds through an AR15 and 100 rounds through an AK. When all said and done, the AR15 is ALWAYS dirtier than the AK even when premium ammo is used in the AR and dirty Wolf ammo in the AK.
That said, is the DI system good enough? Yes. It is not a "white glove test" system, and it can tolerate a fair amount of fowling, with the biggest issue in AR reliability being magazines, followed by an over-ambitious bolt design.
You make my point. Barrels changed in the armory. Not hard with the current platform.
I can see the appeal for the armchair commando who wants to reconfigure their rifle all the time and doesn't want to buy a second complete weapon.
Whatever the case, even with a simple mechanism for barrel change, you're still going to have to rezero and all that jazz. Unless perhaps you have an adjustable front sight mounted on the barrel and have absolutely repeatable torque.
There a review of the ACR floating around the net which makes note of the problems of maintaining zero dismounting and remounting the same barrel. The solution was witness marks, which ends up making the barrel specific to the gun unless you want to rezro.
Frankly, I see this as a more expensive solution to a non-existent problem.
YMMV
I can see the appeal for the armchair commando who wants to reconfigure their rifle all the time and doesn't want to buy a second complete weapon.
Whatever the case, even with a simple mechanism for barrel change, you're still going to have to rezero and all that jazz. Unless perhaps you have an adjustable front sight mounted on the barrel and have absolutely repeatable torque.
There a review of the ACR floating around the net which makes note of the problems of maintaining zero dismounting and remounting the same barrel. The solution was witness marks, which ends up making the barrel specific to the gun unless you want to rezro.
Frankly, I see this as a more expensive solution to a non-existent problem.
YMMV
Shadow 7D
Member
V
You forget a MAJOR issue with roller delayed systems, such as the G3,etc.
They are VERY ammo sensitive, when you have a standard round, and all other rounds are THAT standard in repetitions, then it's ok, change the round, and now you have to re-arsenal all your guns to tune them. Oh and many reloaders don't like the fluted chambers, something about blowing the brass to hell.
As for the AR, I've been there, done that, and if you want to pm the mods, I will be very happy to prove it. It works, I actually saw the Daewoo 200?? with piston ($585 at the local pawn shop)
And I have never rally had an issue with live rounds, mind you end of the day with blanks, it can be a little finicky, but then, how many of you are going to be blowing mags in burst? It works, until something drastically different comes along, I don't think the bean counters are going to do much except send existing stock back to be rebuilt and reissued. Maybe special units will get the SCAR, but then they get to buy what the like anyways, the rest of the Army, hell sometimes I was suprised we were allowed to change our own mag with out supervision. Change configurations with out prior auth and the armorer, naw.
You forget a MAJOR issue with roller delayed systems, such as the G3,etc.
They are VERY ammo sensitive, when you have a standard round, and all other rounds are THAT standard in repetitions, then it's ok, change the round, and now you have to re-arsenal all your guns to tune them. Oh and many reloaders don't like the fluted chambers, something about blowing the brass to hell.
As for the AR, I've been there, done that, and if you want to pm the mods, I will be very happy to prove it. It works, I actually saw the Daewoo 200?? with piston ($585 at the local pawn shop)
And I have never rally had an issue with live rounds, mind you end of the day with blanks, it can be a little finicky, but then, how many of you are going to be blowing mags in burst? It works, until something drastically different comes along, I don't think the bean counters are going to do much except send existing stock back to be rebuilt and reissued. Maybe special units will get the SCAR, but then they get to buy what the like anyways, the rest of the Army, hell sometimes I was suprised we were allowed to change our own mag with out supervision. Change configurations with out prior auth and the armorer, naw.
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The idea that any self loading action remains clean is a serious mistake. However it gets driven, an action that extracts a cartridge from a chamber under it's own power - gas or recoil - will have residual gas blown back into the action no matter what. Only manually operated weapons keep a clean bolt face.
The second mistake is to consider the residual buildup in the action as a major cause, or for that matter, even a potential cause of stoppages. The modern TDP for the M16, with chromed chambers, proper dimensional checking, proven first use powders, and the REQUIRED lube of the cam pin track all contribute to keeping the M16/M4 running. If anything, it's been demonstrated time and again that AR's will run for tens of thousands of rounds without cleaning. Getting dirty will not stop a gun built right. It will keep firing, and the AR demostrates it time and again.
It's when all the wrong things are done than we hear about malfunctions. Going back to the dust tests, if poor maintenance and bad magazines are used, you get poor results. Use weapons and mags in good repair, they shoot better. Please remember the majority of stoppages are from magazine and ammo related causes, and many of the anecdotal stories on the internet involve low power ammo and weapons built without any TDP at all other than a bulk order for all the parts.
For all the complaints DI runs dirtier, no one explains what causes a specific problem that actually stops the action cycling. The bolt carrier and bolt haven't been changed in 45 years to "improve" them or make them more resistant to fouling, and yet that's the #1 complaint brought up in theoretical discussions. When actually tested, it falls far down the list, with mags and ammo sharing the bulk of the severe problems up front.
Just exactly what is it that causes the bolt to jam? Pics, please. Link to an official report listing just how much x.xxx inches of residue built up on the operating parts causes it to become a sludge pile. Finger pointing and namecalling don't make for repeatable results in failure, and again, back to the dust tests. The majority of problems are mag and ammo based, not residue buildup, even when a lot more is added beyond the gunpowder.
It hasn't been a problem since 1968, ask those who have been shooting at us what they think about it.
If we are going it have a better weapon with better subsystems and parts, it's going to take a lot more objectivity, study, and understanding of what it does. Simply repeating street talk and unfounded rumor won't get us there.
The second mistake is to consider the residual buildup in the action as a major cause, or for that matter, even a potential cause of stoppages. The modern TDP for the M16, with chromed chambers, proper dimensional checking, proven first use powders, and the REQUIRED lube of the cam pin track all contribute to keeping the M16/M4 running. If anything, it's been demonstrated time and again that AR's will run for tens of thousands of rounds without cleaning. Getting dirty will not stop a gun built right. It will keep firing, and the AR demostrates it time and again.
It's when all the wrong things are done than we hear about malfunctions. Going back to the dust tests, if poor maintenance and bad magazines are used, you get poor results. Use weapons and mags in good repair, they shoot better. Please remember the majority of stoppages are from magazine and ammo related causes, and many of the anecdotal stories on the internet involve low power ammo and weapons built without any TDP at all other than a bulk order for all the parts.
For all the complaints DI runs dirtier, no one explains what causes a specific problem that actually stops the action cycling. The bolt carrier and bolt haven't been changed in 45 years to "improve" them or make them more resistant to fouling, and yet that's the #1 complaint brought up in theoretical discussions. When actually tested, it falls far down the list, with mags and ammo sharing the bulk of the severe problems up front.
Just exactly what is it that causes the bolt to jam? Pics, please. Link to an official report listing just how much x.xxx inches of residue built up on the operating parts causes it to become a sludge pile. Finger pointing and namecalling don't make for repeatable results in failure, and again, back to the dust tests. The majority of problems are mag and ammo based, not residue buildup, even when a lot more is added beyond the gunpowder.
It hasn't been a problem since 1968, ask those who have been shooting at us what they think about it.
If we are going it have a better weapon with better subsystems and parts, it's going to take a lot more objectivity, study, and understanding of what it does. Simply repeating street talk and unfounded rumor won't get us there.
Shadow 7D
Member
I really don't see much of a change until exo-suits come on line and then it'll be 'how much crap can we make one carry' GAU-123 anyone??? The ammo bearers can carry the extra 15k rounds. Until then, energy weapons or a new propellant, ammunition design (which won't happen cause Hauge) or a dramatic and completely new materials, I think the M16 family is here to stay.
Lets not forget the Brown Bess was the standard for close to 200 years, because nothing new was being done. Advances in metallurgy and ammo design lead to strong enough breach lock, and stable explosive and caps lead to better firing mechanisms that you got the next/new guns.
Lets not forget the Brown Bess was the standard for close to 200 years, because nothing new was being done. Advances in metallurgy and ammo design lead to strong enough breach lock, and stable explosive and caps lead to better firing mechanisms that you got the next/new guns.
Hague isn't a problem, JAG cleared open tip match ammo in the '80's. It still didn't revoke the need for penetrator ammo, and the SOST was made for that.
Two things coming up in the twenty year view, suppressors, and caseless ammo. Long term hearing loss, and the increased ability to acquire them as they can be mass produced in an effective design, means that suppressors are becoming much more mainstream in the military. We won't continue to put up with gunfire diminishing our hearing ability on the battlefield, especially at the team level. We don't need to have our fire give us away, and we can afford it. If we can put a $650 to $1000 optic on a combat weapon, a mass produced $250 can is equally feasible.
The LSAT caseless rounds offer even more of a fighting multiplier. They weigh the less, but give 50% more ammo, making the soldier much more equipped like a squad automatic. There's no dead weight, nothing gets underfoot, there are no extraction problems, you get one less item to reveal a position, as no brass is bouncing around attracting attention. They can be loaded in quad stack vertical magazines, increasing the round count, but making the overall height lower. Magpul already has the patent on that.
The Army already is scheduling battalion level testing, and SOCOM has signed on, too. That implies some real world guns getting into hot zones. Might help explain why the SCAR is no longer interesting. It doesn't give a 50% ammo increase or improve hit probability. LSAT ammo does.
I should have put both those in the first post.
Two things coming up in the twenty year view, suppressors, and caseless ammo. Long term hearing loss, and the increased ability to acquire them as they can be mass produced in an effective design, means that suppressors are becoming much more mainstream in the military. We won't continue to put up with gunfire diminishing our hearing ability on the battlefield, especially at the team level. We don't need to have our fire give us away, and we can afford it. If we can put a $650 to $1000 optic on a combat weapon, a mass produced $250 can is equally feasible.
The LSAT caseless rounds offer even more of a fighting multiplier. They weigh the less, but give 50% more ammo, making the soldier much more equipped like a squad automatic. There's no dead weight, nothing gets underfoot, there are no extraction problems, you get one less item to reveal a position, as no brass is bouncing around attracting attention. They can be loaded in quad stack vertical magazines, increasing the round count, but making the overall height lower. Magpul already has the patent on that.
The Army already is scheduling battalion level testing, and SOCOM has signed on, too. That implies some real world guns getting into hot zones. Might help explain why the SCAR is no longer interesting. It doesn't give a 50% ammo increase or improve hit probability. LSAT ammo does.
I should have put both those in the first post.
Shadow: The ammo sensitivity of the roller delayed blowback designs is over-hyped. To take the PTR91 as an example, it will shoot anything from 110gr to 180 gr .308 rounds, albeit the sweet-spot is with 150gr or lighter, as the recoil starts to escalate and become excessive as you get closer to 180 gr.
The other point is in a fighting rifle, you shoot what you are given. There is no headache of "do I select 55 62 or 77gr round for patrol this time?" You carry what rounds are issued to you, and everyone gets issued the same ammo. Thus, 99% of all G3 rifles shot the 142gr 7.62x51 round, and the majority of M16/M4's shoot the 62gr 5.56x45 round.
The whole swapping weights of ammo and barrels only comes into play in the armchair situation, very rarely in the field.
The other point is in a fighting rifle, you shoot what you are given. There is no headache of "do I select 55 62 or 77gr round for patrol this time?" You carry what rounds are issued to you, and everyone gets issued the same ammo. Thus, 99% of all G3 rifles shot the 142gr 7.62x51 round, and the majority of M16/M4's shoot the 62gr 5.56x45 round.
The whole swapping weights of ammo and barrels only comes into play in the armchair situation, very rarely in the field.
kwelz
Member
Over hyped or not it is still there.
And the military does change the type of ammo they use as technology and fighting doctrine changes.
And the military does change the type of ammo they use as technology and fighting doctrine changes.
Great point about the silencers. I never really had that "epiphany" but it is very smart when you think about it. You know in England they actually prefer that the sportsmen have silencers so as not to bother the neighbors when shooting rabbits. Opposite viewpoint here in the US. Modularity increases efficiency as already stated as you can take a rifle from 14.5" carbine to DMR rifle in seconds or a couple minutes. Whether or not you like it, the "bullpup" design allows a 20" rifle to be as compact as a 16" carbine. The Brits have shown in combat and training that this design definitely "holds its own" in accuracy and performance.
Have they worked through the heat issues with caseless ammo? The ejected brass takes a lot of heat energy with it that otherwise stays with the weapon. You know the RPG has been so integral with our enemies that I feel a modern weapon doing the same thing will be more important in our units than in the past.
Have they worked through the heat issues with caseless ammo? The ejected brass takes a lot of heat energy with it that otherwise stays with the weapon. You know the RPG has been so integral with our enemies that I feel a modern weapon doing the same thing will be more important in our units than in the past.
CapnMac
Member
Suppressing combat weapons, especially give our presumption of a lot of CQB and MOUT in asymmetrical conflicts really makes a lot of sense. Except that adding a suppressor is increasing the OAL, just the thing we have been reducing the better to get in and out of over-full APC and Helos.
That suggests getting the buffer and recoil springs out of the butt stock and somewhere else on the rifle is logical. It also means being able to have finer adjustments between the gross settings on the stock's OAL. Put a provest on over a field jacket, and that adjustment is very nice; being able to tweak that length just a bit would be even better.
I would not be surprised to see a change to a round in the 6-7mm diameter, with a case in the 35-45mm length size. However the trillyards and billyards of extant ammo mitigate against a change. Which is usually the second hurdle caseless ammo faces. That, and the factors of reliability and long term storage--having that cartridge case complicates weapon design, but makes storage very simple.
My bet is that, when caseless is adopted, the first iterations will be a hybrid, with a casehead only, to carry and index the primer. I'd wager the rounds will be "telescoped" too.
But, it would likely take a full package deal to not be another incremental change in technology. Like, say, a 6.5x40 with a longitudinal magazine feeding top to bottom in a fully ambi carbine with integral suppression. Maybe and "inverted" bolt with much of the mass surrounding the barrel, and ahead of the breach. Which would be handy for short-stroke gas operation.
But, that's nothing but woolgathering in my head, a nothus-mix of prior-art ideas from M-1 Carbine, P90, Calico, and the like mashed together. Hopefully, smarter people than I are working on this.
That suggests getting the buffer and recoil springs out of the butt stock and somewhere else on the rifle is logical. It also means being able to have finer adjustments between the gross settings on the stock's OAL. Put a provest on over a field jacket, and that adjustment is very nice; being able to tweak that length just a bit would be even better.
I would not be surprised to see a change to a round in the 6-7mm diameter, with a case in the 35-45mm length size. However the trillyards and billyards of extant ammo mitigate against a change. Which is usually the second hurdle caseless ammo faces. That, and the factors of reliability and long term storage--having that cartridge case complicates weapon design, but makes storage very simple.
My bet is that, when caseless is adopted, the first iterations will be a hybrid, with a casehead only, to carry and index the primer. I'd wager the rounds will be "telescoped" too.
But, it would likely take a full package deal to not be another incremental change in technology. Like, say, a 6.5x40 with a longitudinal magazine feeding top to bottom in a fully ambi carbine with integral suppression. Maybe and "inverted" bolt with much of the mass surrounding the barrel, and ahead of the breach. Which would be handy for short-stroke gas operation.
But, that's nothing but woolgathering in my head, a nothus-mix of prior-art ideas from M-1 Carbine, P90, Calico, and the like mashed together. Hopefully, smarter people than I are working on this.
A reflex type suppressor add very little in length.
Much as I dislike bullpup designs, that neatly addresses the length issue, allowing for a full length barrel with a short overall weapon. Forward ejection or caseless neatly deal with the right/left issue.
Then again, it's still just a bullet thrower, and that whole concept is just about played out. The ACR test showed that about the only way to significantly increase hit probability over the current rifle is to go to an explosive projectile. The XM-29 and XM-25 are a direct result.
The first 5 XM-25 are supposed to go to Afghanistan any day, with another 30-40 to follow shortly. The XM-25 is slated to enter service in 2012 as a special purpose weapon. But as weight and cost come down as the technology matures it could very well become the next infantry weapon.
Note that this concept is being pursued by other countries as well. Korea has its first export customer for the K-11 (UAE IIRC).
Much as I dislike bullpup designs, that neatly addresses the length issue, allowing for a full length barrel with a short overall weapon. Forward ejection or caseless neatly deal with the right/left issue.
Then again, it's still just a bullet thrower, and that whole concept is just about played out. The ACR test showed that about the only way to significantly increase hit probability over the current rifle is to go to an explosive projectile. The XM-29 and XM-25 are a direct result.
The first 5 XM-25 are supposed to go to Afghanistan any day, with another 30-40 to follow shortly. The XM-25 is slated to enter service in 2012 as a special purpose weapon. But as weight and cost come down as the technology matures it could very well become the next infantry weapon.
Note that this concept is being pursued by other countries as well. Korea has its first export customer for the K-11 (UAE IIRC).
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