Gas piston rifle testing.

[SHvar]

Articles
2 Bushy gas piston rifles, and 4 M-4s, 35,000 rds.
http://www.policemag.com/Articles/2007/11/Bushmaster-Gas-Piston-Rifle.aspx
H&K416 Vrs LMT MRP gas piston rifle.
http://www.defensereview.com/lmt-mrp-pistonop-rod-system-vs-hk416-2000-round-head-to-head-test/

Videos
Next, water testing, LWRC, H&K416, Bushy/Remmington/Magpul ACR.
LRWC water test.
http://www.youtube.com/watch?v=JMZX5WO1uSk
H&K416 water test
http://www.youtube.com/watch?v=AGwkHktkTxU
Bushmaster/Remington, Magpul ACR submersion test.
http://www.youtube.com/watch?v=7rWvCc77wvk
These were not cut and or fixed to favor one rifle or another.

 

[P.B.Walsh]

Looks like a GP rifle takes the cake!!

 

[Grantman]

Noticed the police link wasn't working. Managed to find the new link

http://www.policemag.com/Channel/Weapons/Articles/2007/11/Bushmaster-Gas-Piston-Rifle.aspx


Some further links that further cement the situation

Small Arms Review magazine stress evaluation of POF 416 gas piston rifle vs DI
http://www.pof-usa.com/articles/P416Torture.pdf
http://www.pof-usa.com/POF416.pdf



Army dust test with DI and GP rifles + further info, army times reporting
http://www.armytimes.com/news/2007/12/army_carbine_dusttest_071217/
http://www.armytimes.com/news/2007/02/atCarbine070219/

and for a bit of straight talking http://www.madogre.com/interviews/Hate_the_AR15.htm

 

[rangerruck]

great links; according to the one article, the max temps, after 1000 round dump, for the chamber and bolt face on the piston drive, was 122 for the bolt, and 131 for the chamber. Awesome.
boht articles together, say the piston drive has fired over 20k rounds without a hitch, and went the first 9k rounds, without a clean or lube job. Also very awesome.

 

[MCMXI]

The HK416 vs. the Colt AR test was very interesting ... water is basically incompressible, so are we to assume that the water in the gas tube exerted sufficient force on the gas key, carrier and bolt and consequently the upper receiver causing it to fracture and blow the magazine out of the lower? Somewhat like hydraulic lock in a car/truck engine resulting in bent connecting rods ... hmmm ... I need to think about this. Another thing I noticed for the ACR tests was that the bolt was forward for all of the submersions. The bolts on both the HK416 and Colt AR were back for the tests prior to submersion i.e. the slide release was pressed while the rifle was submerged. The ACR was only submerged for a couple of seconds too ... kind of a lame test if you ask me.

One nitpick re Nick Jacobellis's article about the Bushmaster's gas piston AR ... he begins the article stating ...

"Bushmaster's update of the tried-and-true M4 design is accurate, easy to maintain, and ready for hard duty."

If I were his editor, I would have changed the sentence to read ...

"POF's first generation update of the tried-and-true M4 design, which is licensed to Bushmaster, is accurate, easy to maintain, and ready for hard duty."

Let's give credit where it's due!!

Anyway, I like my POF even more now ... even though one wasn't tested underwater.

 

[THE DARK KNIGHT]

So basically, it took 60 years for the west to admit that Kalashnikov was onto something...

 

[MCMXI]

So basically, it took 60 years for the west to admit that Kalashnikov was onto something...

I was under the impression that the Germans or possibly the Italians "invented" the gas piston rifle and that the AK was heavily influenced by the gas system and layout of the StG44.

From Wikipedia ...

"The AK-47 is best described as a hybrid of previous rifle technology innovations: the trigger, double locking lugs and unlocking raceway of the M1 Garand/M1 carbine,[7] the safety mechanism of the John Browning designed Remington Model 8 rifle,[8] and the gas system and layout of the StG44. Kalashnikov's team had access to all of these weapons and had no need to "reinvent the wheel",[9][10] though he denied that his design was based on the German Sturmgewehr 44 assault rifle."

 

[lipadj46]

So basically, it took 60 years for the west to admit that Kalashnikov was onto something...

There were gas piston rifles before the Kalashnikov. The US issued 2 battle rifles with gas pistons before the M16.

 

[Grantman]

So basically, it took 60 years for the west to admit that Kalashnikov was onto something...

Some people would still refuse to recognise the reliability advantage. But to correct, the west has been churning out gas piston designs exclusively with the exception of a couple of old french rifles, the m16 and perhaps a couple of unknowns (can't forget the roller delayed design either).

 

[rangerruck]

I think an early 1900's browning design, was ripped off by kalashnikov anyway.
and I think it was a piston drive as well.

 

[rcmodel]

So basically, it took 60 years for the west to admit that Kalashnikov was onto something...

Not exactly.
1892: John Browning patented the first gas operated self-loading firearm.
1895: Colt / Browning gas-operated machinegun was invented.
1914: Russia bought a bunch of them.
1918: The gas-operated Browning BAR was fighting in WWI.
1919: Mikhail Kalashnikov was born.
1936: The gas-operated M1 Garand was adopted.
1945: Little Mikey invented the AK-47.
1947: It was officially adopted by the Russian military.

rc

 

[ClickClickD'oh]

Every time the piston crowd brings up the widely debunked HK video I laugh a little harder. Just sad guys.

Bolt face temps after 1,000 round mag dumps?

M-4 failing after being intentionally kept in sand storms WITH THE DUST COVER OPEN?

Really pathetic guys.

 

[mp5a3]

John Browning could outdesign ole Mikael (sp) with his pinky finger. If he was alive today it would be interesting to see what he could dream up.

 

[MCMXI]

Every time the piston crowd brings up the widely debunked HK video I laugh a little harder. Just sad guys.

Could you elaborate on that and provide sources? I'm not planning on submerging my POF anytime soon but I am interested in facts rather than fiction so if the HK test is flawed then speak up.

Thanks.

 

[rcmodel]

Every test I have seen has been run with HK using different rules (Or slight of hand if you will) then they used on the M-16.

The mud test was done sans mag and the dust cover open on the M-16.
The HK was buttoned up tighter then your fly.

The HK was picked up out of the water muzzle down so the water could run out of the bore, and it may have even had the bolt locked open so there was no chamber seal to keep the water from running out.

The M-16 was removed from the water bolt closed and muzzle up, and the bolt was never cracked to break the seal & let the water out of the bore & gas tube.
(Standard practice on a submerged M-16 since Vietnam BTW)

In other tests, I have seen the mud or sand packed on the M-16 with the bolt cover open and no mag. The Piston gun, of whatever make, is always closed up tight with a loaded mag in the mag well.

rc

 

[ClickClickD'oh]

Could you elaborate on that and provide sources?

Take the time to search this forum for "HK" and "Video" and you'll get many posts like this one by Dr. Tad.

The video is an advertising scham perpetuated by HK. Nothing more.

 

[MCMXI]

The HK was picked up out of the water muzzle down so the water could run out of the bore, and it may have even had the bolt locked open so there was no chamber seal to keep the water from running out. The M-16 was removed from the water bolt closed and muzzle up, and the bolt was never cracked to break the seal & let the water out of the bore & gas tube.
(Standard practice on a submerged M-16 since Vietnam BTW)

Are you sure about that ... it looks like the Colt came out butt first ... you can see the muzzle clear of the water in the second photo. The Colt barrel (probably 16") appears to be longer than the 10" HK barrel, but by the time the trigger is pulled, no water is seen coming out of either barrel.

Colt ...

Colt ...

HK ...

Take the time to search this forum for "HK" and "Video" and you'll get many posts like this one by Dr. Tad. The video is an advertising scham perpetuated by HK. Nothing more.

The video may or may not be a "fraud" to use Dr. Tad's phrase but it'd take a lot more than a member's theories and speculation to convince me. You'd think that all of the DGI AR manufacturers would have conducted their own tests to debunk the HK video. The whole point about conducting any experiment and publishing the results is that the experiment can be repeated and the results verified. This would be a very easy test to reproduce for companies such as Bushmaster, DPMS, Olympic Arms etc? Have you seen any results from those companies. If not ... why not?

 

[MCMXI]

According to HK's video, the SOCOM test requires the following (not verified).

Requirement for SOCOM

Test A Procedure:

1. Bolt open, magazine with 1 round inserted.
2. Weapon immersed in water tank 3-4 inches below surface. Allowed to fill (no bubbles).
3. Bolt closed (under water).
4. Weapon raised from water tank.
5. Weapon permitted to drain for 7 seconds maximum.
6. Chambered round fired.

Test B Procedure:

1. Bolt forward with 1 round chambered.
2. Weapon immersed in water tank 3-4 inches below surface. Allowed to fill (no bubbles).
3. Weapon raised from water tank.
4. Weapon permitted to drain for 7 seconds maximum.
5. Chambered round fired.


No mention of muzzle up or down as the rifle is clearing the water but the rifle has to be fired within 7 seconds. Perhaps this is where HK figured out they'd have an advantage. In both cases, the HK and Colt are fired within two seconds of being out of the water. If they waited four, five or six seconds it might be a different story and maybe no story at all. I would imagine that most of the water would be expelled from the Colt (the gas tube in particular) after five seconds. It's also possible that there are some folks out there that can't afford to have "the bolt cracked" or wait five seconds before they can take a shot.

I could care less about this test other than I like facts rather than fiction. As is so often the case on this board, no facts are presented, just speculation and BS!! I try to avoid both.

 

[Grantman]

Every time the piston crowd brings up the widely debunked HK video I laugh a little harder. Just sad guys.

I'd be willing to wager that it is no more fraudulent than the LWRC http://www.youtube.com/watch?v=7rWvCc77wvk In other words not fraudulent at all. Sure there are cuts here and there in the HK video but so what. All the cuts do is allow skeptic's imaginations to run riot rather than proving anything whatsoever.

M-4 failing after being intentionally kept in sand storms WITH THE DUST COVER OPEN?

Really pathetic guys.

Why? Did you want the M4 babied with special treatment?

 

[R.W.Dale]

While I don't see the need for a gas piston for my AR's I do recognize their importance to others, even if like myself it's only for the pure entertainment value such topics provide.

 

[ClickClickD'oh]

You'd think that all of the DGI AR manufacturers would have conducted their own tests to debunk the HK video.

Why would they want to? Are HK416 sales going to cut into their sales? No.

Why bother.


PS. Every single AR/M4/M16 obstruction failure I've seen, which is more than a few thank you NTC, involves the left side of the reciever departing. Not the right side as in the HK video. Don't take my word for it. Do some research yourself. Magazine goes pop, left side fails. Like Clockwork.

Did you want the M4 babied with special treatment?

Yeah, closing the dust cover is really babing a gun... That's rational...

And yes Grantman, chopping out parts of a taped "test" is a pretty significant indication that the test did go they way they want to represent it.

 

[MCMXI]

Why would they want to? Are HK416 sales going to cut into their sales? No. Why bother.

Slander, misrepresentation, fraud etc. come to mind plus the marketing appeal of meeting SOCOM requirements. Also, how about military sales/contracts and the general perception by the gun-buying public. HK isn't the only gas piston AR type available ... a number of manufacturers are getting into or are already in the gas piston market. How about companies that offer gas piston upgrade kits? Bushmaster offers a gas-piston AR (POF design) and charges a premium for it. How about some fact-based benefits to accompany the added cost? The fact that the mainstream AR manufactures haven't conducted and published results from similar tests gives me reason to wonder if submersion tests do indeed present a tough challenge for DGI rifles.

 

[Grantman]

Yeah, closing the dust cover is really babing a gun... That's rational...

And yes Grantman, chopping out parts of a taped "test" is a pretty significant indication that the test did go they way they want to represent it.

If the other weapon systems have their dust covers open then the M4 shouldn't receive special treatment and have it closed. When it comes to reliability testing the goal isn't to protect the firearm.

Cuts in video sure don't help, but I very much doubt the HK is any more unrepresentative than the LWRC video.

 

[ClickClickD'oh]

Slander, misrepresentation, fraud etc.

It's only slander if it's believable.

How about some fact-based benefits to accompany the added cost?

Okay, what are the fact based benefits that offset the increased cost?

So far they appear to be:
1) If you dump more ammo through the gun than anyone has ever carried inot combat the bolt will be a couple of degrees cooler
2) If you wander around in a sandstorm with your dust cover open and your rifle unprotected you might get your weapon functioning faster.
3) You can star in heavily edited HK promo videos.

You see, I don't count rifle funtioning in conditions that would kill the operator, or shooting more ammo than god can carry to actually be benefits at all. That's wow gee factor.

The fact that the mainstream AR manufactures haven't conducted and published results from similar tests gives me reason to wonder if submersion tests do indeed present a tough challenge for DGI rifles.

Anyone who fires a weapon with an obstructed barrel is going to have a really bad day. DI, piston, bolt or muzzle loader. Same thing happens.

 

[MCMXI]

It's only slander if it's believable.

At this point, the video is more believable than the theories, conjecture, speculation and anecdotal evidence from anti gas piston THR members. HK is a company with a reputation for excellent products. I have a hard time believing that they'd risk their reputation on a lame video since the tests performed are easy to repeat.

Anyone who fires a weapon with an obstructed barrel is going to have a really bad day. DI, piston, bolt or muzzle loader. Same thing happens.

The SOCOM test doesn't mention an obstructed barrel and based on the videos, there's a very good chance that there wasn't any water in either the HK or Colt barrels.