Riddle me this Batman

H

HKGuns

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Going to try a different angle on the DI vs. Piston thing to see what you think.

I've already stated I own and love my DI rifle and will soon purchase a piston as well. I just find the debate interesting, please, lets keep it nice.

Here are the reported contenders in the Army's IC competition:

Colt: CM901 multicaliber rifle (5.56mm – 7.62mm) -DI
FN Herstal: SCAR-L 5.56mm -Piston
HK USA: HK416 5.56mm -Piston
Remington: Adaptive Combat Rifle multi-caliber -Piston

Lots of other, smaller players dropped out because of the long procurement timeline and their relatively low capitalization levels couldn't support such a drawn out affair. (S&W being one.)

Each competitor could only submit one entry into the competition, so you can figure, within the given the requirements, it would have to be their "best". (HK couldn't use the G36 without being eliminated.)

What do the DI guys say about 3/4 of the contestants being piston rifles?

- HK doesn't have a DI alternative as they started out trying to engineer a better rifle. (By most accounts they succeeded.)

- FN certainly has the capability to produce a DI AR as they've sued the US Government over Colt's sole sourcing. Yet, they chose to enter the SCAR.

- Remington sells DI rifles, yet they chose to enter the ACR?

Doesn't this really end the debate on which system is better for this use case (Military)? Or, are you going to suggest these companies are all stuipid and entered a sub standard rifle to win this competition?

I still maintain for home or recreational use either will work just fine and it is more a case of what are your requirements.

Edited to add: Let's see if we can keep this from getting locked please!
 
What do the DI guys say about 3/4 of the contestants being piston rifles?.............Doesn't this really end the debate on which system is better for this use case (Military)?
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No, this doesn't end the debate. Colt has been producing the M16 DI system for a long time. It takes a lot of money to produce an item in such quantities. If you look at all the AR/M16 clones out there closely you'll see they are really no different then the Colt.

How are you going to compete with Colt making a rifle that is in fact a clone, considering Colts already has the tooling to mass produce the rifle.

Machinery is considered a "fixed cost" in doing business. Meaning you have X dollars to spend on machinery, the more widgets that machinery produces the less cost of manufacturing that widget. Colt has over 4 decades of production to spread the cost of machinery, new companies have to figure in the cost of machinery to compete.

Kind of like Lights, you have to pay a monthly light bill. The more products you sell, the less cost of each widget needs to be set aside to pay that light bill.

FN and the others has been making rifles a long time. They have other products to help soak up the cost for their widgets, but even still, cost wise they cannot compete with Colt.

If one company has a product that's been used for 4 decades and can produce that same product at X cost, why would a country who is in the process of cutting half a trillion dollars from their budget switch to a system that besides being 5 times the price and no proven benefit over the cheaper product.

I realize this is a boring response, but Managerial Accounting is a boring subject but that is in fact what we are discussing here.
 
If one company has a product that's been used for 4 decades and can produce that same product at X cost, why would a country who is in the process of cutting half a trillion dollars from their budget switch to a system that besides being 5 times the price and no proven benefit over the cheaper product.
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I enjoy your posts and respect your opinions but I think this statement is a little exaggerated. 5 times the cost? No proven benefit? I recently purchased a LMT piston AR. I have run about 500 rounds through it and have yet to clean it. Well I have cleaned the barrel. The bolt and carrier on this thing is so clean it is ridiculous. Not saying it is better but that is a fact. Secondly, I am keeping a close eye on any sign of carrier tilt. They (LMT) have added these small sled like rails on the bottom and back of the carrier to compensate for it. The piston weighs next to nothing so that is a non factor. Thirdly, and I don't think it can be argued, the piston is a better system for SBR and suppression. While the jury may still be out on this on going debate, I don't understand the constant bashing of piston systems. Whether it is better or not, the piston driven AR is here to stay. Those that want one and are willing to pay the extra buck, will. Those that don't, won't.
 
I could not agree more with kraigwy.

No company is going to enter a colt clone in a competition against a colt original, unless they thought they could beat colt on price. As kraigwy said, that is very unlikely given the numbers of weapons colt has produced. No one can make a Colt AR-15/M4/M16 as efficiently as Colt.

There is a political aspect as well. Foreign arms makers are sensitive to the politics of selling arms to the US military. I can imagine the possible political/media "scandal" that could come from HK or FN (foreign companies) selling a Colt clone (Colt being an American company). HK and FN don't want to be demonized by the press...
 
I don't recall I have ever "bashed" the piston system. I have said I don't see the huge advantage.

First of, my AR shooting is in the Competition Venue as in CMP/NRA High Power. The CMP doesn't reconize the piston driven ARs as a service rifle in their matches so in reality its a non issue to me.

Second every one talks about test for the military. We are in one war, just finished a second war, we have millions of M16/M4s out there that would need to be replaced, all this at a time when the military is getting .5 trillion cut from their budget.

I just can't see enough of a benifit of switching rifles to a more expensive rifle when there has been no clear proof one is better then the other.

You're not going to make everyone happy but when surveys of those invovled in combat with the rifle say 80% of the end user are happy with the M16/A4, I just can't see the justification of the cost of changing.

As an individual you choose the system based on your needs. As mention, I can't use a piston driven AR. Its the same as Semi Vs Revolver. It's a non issue if you're shooting an ICORE match. It doesn't matter if you think a revolver is better then a semi, or vis versa, ICORE is limited to Revolvers.
 
Doesn't the piston operation keep it running cooler? Less cyclical heat loading will significantly improve the life of a barrel, all other variables being ignored. It should also keep the rifle shooting more consistently for longer periods of extended fire (theoretically). Definitely correct me if I'm mistaken, I've never used a piston AR and my knowledge on them is only from literature.
 
Doesn't the piston operation keep it running cooler?
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Got me, I've never fired one that much either, and I doubt in my situation today I'll ever need to shoot any gun enough to get to the point that heat makes a difference.

However in my younger years I've shot the DI system (M16a1) to the point the barrel and gas tube turned red and it still kept going. I've shot a lot of rounds out of a M16a1 in a very short period of time and it never quit. The only gun I've fired to the point it got so hot it quit was an M60. It has a piston.

My point is, is there enough difference to justify the cost? We have millions of DI M16/M4s out there, sure we will need replacements and replacement parts, but to switch to the Piston Rifle would require not just replacement parts, but the replacement of the millions DI guns we already have.

Even if the cost per rifle was the same I don't think this country can afford it in todays economy.
 
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They missed the single gun that would put it all to rest.

Robinson Arms XCR

Needs a bit of improvement, but the basic design is solid as hell, ergonomics the best of any of them (and I have tried them and own a DI as well).

Can change caliber and barrel length to suit the mission, and it maintains its accuracy.

Who knows what the Army wants, but what they will keep doing is DI.

As stated, DI is great for a lot of stuff (certainly civilian use) but for the military the Long Stroke Piston is the best (and not the Tappet type that most use, alas Short Stroke Piston)

But then the M1 would have been better with a clip and so it goes.
 
Kraig hit the nail on the head.

You like DI or Piston guns or neither... it all comes down to cost. I don't see our military switching to a different rifle that is much more expensive.. that literally does nothing better.

A piston does run cooler in the chamber... but hotter at the barrel. Even still a DI chamber is still cool enough to shotgun the BCG and hold it in your hands.

If you really truly believe piston op rod is really better.. I will let you go... im done debating it.. I know what I've seen and done with my own eyes and hands.. that is enough for me... what you really need to look at is what Kraig is saying.

Even IF the piston guns run slightly cooler and cleaner.... it comes down to cost vs. benefit. The M16 has been used with great success... a piston conversion of it.... really isn't bringing all that much to the table in advantage to make it worth the billions of dollars they would need to spend to replace it.

Will we see certain units with the higher $$ sticker guns... I'm sure. SOCOM will get whatever they want really, but even they saw little significance in switching to the SCAR and dropped it. I don't see our military spending the $$ to trying to make a piston op rod gun... the standard issue, just based on cost vs. benefits.
 
You guys aren't thinking about this the correct way.

You are thinking about it from the perspective of a consumer. As a consumer, you look for "the best". The problem is, that doesn't exist except in Marketing.

At its basic form a rifle is a means to convert chemical energy to kinetic energy.

How a designer gets there is a function of engineering compromises and trade-offs.

Each company makes a choice of what compromises best suit the design specifications for the RFQ. Those designs are fully tested and refined and finally offered up for evaluation.

It is impossible for a company to just pick "the best" design and run with it even if such a thing actually existed. There isn't a Wal-mart of engineering designs out there that you go and pick up a Short Stroke Piston or a Delayed Roller Locking off the shelf and drop it into your rifle and start running.

So as to the question of why other companies didn't "pick" DI for their rifles. They didn't have a choice, they had to go with designs that they have engineering testing/design experience with. If you look at the designs in detail and compare them to other historical offerings from those companies, you will be amazed at how close they are to what is already out there. Look at the guts of a FN SCAR and a FN FNC.

Colt is the ONLY company that has any experience DESIGNING DI rifles. All the other companies that "make" DI style rifles are only assembling components being produced by various contractors for Colt and FN, not designing components. Even FN is making parts off of prints provided from Colt via their government contract.

Colt has very little experience with designing and building piston rifles and as such, they put their best foot forward with the design they know the best. As did all the other competitors.

As an aside, if you look on the "Trash Heap of History", there are signficantly more "piston driven" failures/abortions than those that used DI.
 
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Kraig is correct. And since the DoD reported a year or so ago that they saw no benefit to piston systems, I think that sets the stage for the tests, and people will be complaining for years about how the tests were rigged and the others were really superior to the M16/M4, etc, etc.

Happened before, it will happen again. In the 1960s, Armalite presented the AR-18 for consideration, but it was rejected because the military had just adopted the M16. The first time I heard of the AR-18 was in 1976, a friend of mine had an AR-180 (semiauto civilian model) that he went on about, and his conspiracy theories would do a movie scriptwriter justice. Hey, it's just economics!

In 1914, the British adopted the Pattern 14 Enfield rifle because it and its cartridge were clearly superior to the SMLE rifle, but economics and the sudden onset of hostilities put off the adoption of a new infantry rifle and cartridge. In 1903, the US changed to the 1903 Springfield rifle and .30-'03 cartridge, but before the rifles were in full deployment we switched the cartridge, and when we did get into WW1 we sent the M1917 to Europe as well as the M1903. In the 1930s, the M1 was adopted as the new service rifle, but political haggling kept it from being fully deployed until 1943 (the middle of a war), so we played around with other weapons, like the 1941 Johnson. In 1953, the US realized that our "greatest battle rifle" was outdated, and tested several alternatives, but due to political pressure we ended up adopting an updated version of the same design, only to have to replace it within 7 years (the shortest-lived service rifle in US military history). I am pretty sure no one wants to have an aborted weapons system overhaul.

In order for the US military to change the current weapon system, the proposed weapon will need to demonstrate that it is superior to (not just as good and different from) the AR15/M16/M4 platform. That usually happens after we get our collective tails kicked in a major battle or war. Since that hasn't happened in a manner directly atributable to the weapon system itself, it will take a while longer for the weapons system to be changed. It's not that the others aren't good, they just aren't better than the M16/M4 and we probably aren't looking for a change right now.
 
The criteria for submitting a gun for trial specifically stated that they would have to be a substantial improvement over the existing M4. Piston isn't, but the LSAT is.

Piston uses the Stoner control layout, barrel extension design, and overall format, just changing the DI portion of moving the bolt to operating rod with piston on the barrel. Even the magazines and furniture are largely the same, so are the sights and optics, much less the ammo. Given military use, exactly what is the superiority of piston - expressed in numbers? Like accountants, if you can't empirically demonstrate a clear superiority in some quality of reliability that can be numerically pinned down, then it's not.

Mean rounds to failure, number of stoppages per thousand, and how many more hits on the enemy per thousand?

The LSAT does offer a measureable superiority because it carries more ammo for the weight, about 40% more. That means the soldier fires more ammo more often, and more bullets flying through the air mean more hits from the 50% of bullets that were never actually aimed at a specific enemy - he just stood up at the wrong time.

Goes to just what kind of criteria the Army is testing, and piston isn't the big decider, it's something else - number of hits. Where the piston is located is just one part of the total design concept. In our experience, who's to say that DI can't be modified and perfected for full auto fire? I don't see where it's really been addressed, because to get there with existing firearms, most designers revert to the cheaper decision as dictated by accounting - make it a piston gun and get it developed quicker. That gets you a gun with less cost sooner that can more likely pass a test, rather than go thru the expense of developing something that they apparently find too challenging to bother with.

It's no wonder the M16 was designed by an aerospace engineer with the facilities to examine most of the dynamic facets of the design, with a team of well educated and trained engineers who understood multidisciplinary science. Armalite had some serious resources and put more than ten years into development.

All the piston designs submitted just copied his work and finessed one part. How clever is that?
 
Not to put words in the OPs mouth, but I didn't get the impression his post was about whether or not the military was going to switch service weapons. I believe he was saying because 3/4 of these companies were offering piston ARs it proved the piston was a better system. Again, I am not saying it is or isn't either way. The subject has been pretty well beaten to death over the last year.
 
Well our military IS a consumer. They will be... and in a way we will be.. fronting the money for said design.

With everything going on in this country.. and recessions.. and budget cuts.. I really don't see the military dropping the time and money on replacing millions of DI rifles for anything that isn't a much better performer.

Even when you look at all the new rifles in the mix... it is pretty safe to say they aren't a break through design.. more simply they are just a modified design of Stoners.

Stoner originally had a gas piston Op rod design.... it isn't new. However DI worked well and used less parts.. making the gun simpler.

The piston guns I spent time with on trial ranges for manufacturers... didn't do anything a normal DI rifle wouldn't do. Any failures I ever personally had with either design.. came down to mags... or orings that needed replacing. I will say however I have seen a few guns carried in to our gun smith at work experiencing issues with carrier tilt, it does happen, but a lot of new designs are addressing it.

Tirod is probably one of the best people on this forum to talk it over with. His knowledge shows in almost every single post he does on the matter. He is correct in saying that the new guns submitted are nothing drastically new... just 90% of what we are already using. Basically take a AR lower, put on a monolithic upper with a gas piston op rod modification, and you have most of those guns. They perform the same and do the same job as DI AR's already in use. So even with out my person bias... I really don't see the military accepting one based on the cost vs. the benefits... or lack there of.
 
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Yes. The military is the consumer.

That is why they are trying to figure out "the best" by submitting a RFQ and asking companies to submit their designs.

I was answering this question:

"Doesn't this really end the debate on which system is better for this use case (Military)? Or, are you going to suggest these companies are all stuipid and entered a sub standard rifle to win this competition?"

Making the assumption that there is a "best" design was what I was trying to point out as incorrect.

There is no such thing.

There are compromises that best suit a particular set of criteria, but that is about as far as you can go.
 
No company is going to enter a colt clone in a competition against a colt original, unless they thought they could beat colt on price. As kraigwy said, that is very unlikely given the numbers of weapons colt has produced.
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but even still, cost wise they cannot compete with Colt.
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Not only is it VERY likely, the 1998 FN lawsuit against the Army was because FN COULD compete with Colt on price, in fact they sued for the chance. Colt was concerned so they started lowering prices after raising them to over $1,000 per rifle. The suit was eventually dismissed because the Army signed a sole source deal, the result of another law suit brought by Colt. FN never had the opportunity to compete on price, although it would appear they were and are more than capable.

I'd suggest a little reading and education on the subject that will toss that argument out the window. Besides, do you think it is any less expensive to design a completely different rifle and ramp up production of said alternative? Especially when you're already producing a DI version?

Click and read please

Doesn't the piston operation keep it running cooler? Less cyclical heat loading will significantly improve the life of a barrel, all other variables being ignored. It should also keep the rifle shooting more consistently for longer periods of extended fire (theoretically). Definitely correct me if I'm mistaken, I've never used a piston AR and my knowledge on them is only from literature.
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Yes it does. Initial acquisition cost is only PART of the total cost picture. The ongoing cost of how often you must service and maintain the rifles is a larger portion of the total cost picture over the life of a rifle. Barrel and bolt life play a SIGNIFICANT role here if you're concerned about the total cost of ownership.

Not to put words in the OPs mouth, but I didn't get the impression his post was about whether or not the military was going to switch service weapons. I believe he was saying because 3/4 of these companies were offering piston ARs it proved the piston was a better system.
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Mostly correct. You can assume since three of four smart companies submitted a piston design as their "best" alternative that this is the case. I was more interested in the discussion this angle on the subject would create. We can all pretty much guess why Colt is the only company that chose to submit a DI rifle with improvements. NO, this is not about whether a replacement will be selected.
 
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Doesn't this really end the debate on which system is better for this use case (Military)?
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No, why would you want to offer an alternitive to something that will beat the pants off you like the M-4 has.

When you're talking about Managerial Accounting, everybody makes widgets.
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Only as an under-grad, in grad school they are called "Sprockets".

Jim
 
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