Mixed news

Well, here we go again. The AK is reliable as all get out. It is also inaccurate as all get out. It probably doesn't help that the average Taliban probably believes that if Allah desires the shots to hit, they will; who needs sights? That being said, ever see a slow motion film of an AK being fired? That barrel visibly vibrates and slings bullets all over the place. And don't even get me started on the effect on accuracy of the loose tolerances that make it so reliable. But then, it is basically a suppressive fire magazine fed light machine gun.

Whatever the problems are with the Stoner direct gas impingement system, the answer is NOT to simply put a piston on that existing weapons system. In full auto fire, because of the way that the upper receiver, bolt, bolt carrier, and barrel extension are designed, piston systems are guaranteed bolt breakers. Our good friends at Knight Armament have fired millions of rounds in both systems and discovered that the gas system pushes the bolt FORWARD just enough to disengage it from the locking recesses in the barrel extension. That really cuts down on the wear and stress on the locking lugs on the bolt and keeps them from breaking.

Piston systems will probably work fine for years in a semi AR. But in the full auto military version, it is a BAD idea.

If the Stoner system is to be replaced, it MUST be with a ground-up design. Not some piston system grafted onto the current design. I'm talking about you, H und K. You and your over-priced, not gonna sell it to civilians anyway, HK416.

I should have explained further that the AR piston systems simply slam the bolt and bolt carrier straight back (no gas enters the upper, pressurizes it momentarily, and pushes the bolt a bit forward, you see), with the locking lugs exposed to great stresses as they impact the barrel extension and slide (in contact therewith) and move. It is a much cleaner system, obviously, but it results in broken bolts in high volume fire.

The New York Times turns out to have an RSS feed for C. J. Chivers, who wrote the blog post about Afghan shooting which is the main source for the Defensetech article you linked to. It's a bit inaccessible (I had to guess the URL); so for the benefit of other readers, it's:

http://atwar.blogs.nytimes.com/author/cj-chivers/feed/

If piston based systems are so destructive on bolt lugs why didn't it break the bolts of the old BAR, the ultra reliable AK, or any of a number of other full auto weapons. Sounds more like a problem with the tempering of the bolts being used, or a reduction in locking lugs to speed up the weapon.

As it is the last time I checked the M4 like the M16A2 had no full auto fire system. It was dropped for an even worse tri-burst system back in the late 1980s. Most fire with the M4 or the M16 today is semi-auto and intended as aimed fire not spray and pray.

The M4A1 in service today is safe-semi-auto, just like the M-16A1 of yesteryear. Burst is found only on the M-16A2, which is getting to be a rare sight indeed in the Iraq/Afghanistan theater.
Also, this test used the recommended cleaning and lubrication that is found in the as issued FM for the weapon that is years out of date. The M4 works best when it is heavily lubricated, and the dust cover is kept closed. I personally know of an M-4 that has fired over thirty one thousand rounds and has never been cleaned once, just heavily lubed.
http://www.ar15.com/content/swat/keepitrunning.pdf

James:

Compare the massive locking lugs on an AK bolt (or any of those others you mentioned) with the tiny locking lugs on an AR bolt. There's your answer right there. You don't have to believe me. Google is your friend. The research I'm talking about was also done by Reed Knight. He, you know, worked with Eugene Stoner toward the end of Stoner's life.

Mark:

If M4s weren't being used in full auto, there would have been no reason to change the barrel profile like they did for the M4A1. You can't fire enough rounds semi-auto fast enough to get the barrel hot enough to burst.

What I want is an H&K G3 or 33 rescaled to the 6.8SPC cartridge. The H&K roller-delayed blowback action doesn't have ANY of the problems associated with gas operation (piston or Stoner schemes). I admit the chamber fluting makes the fired hulls look a bit strange, and the blowback action seems to take 2-3% off the muzzle velocity (you can get your velocity back by substituting a polygonal-bore barrel for a standard groove-rifled barrel). As for the few extra ounces of overall weight (mainly due to that heavy bolt) if you plan to shoot full-auto that extra weight is pretty much beneficial, and the roller-delayed blowback action is fantastically reliable.

The answer the PTR 32

http://www.ptr91.com/ptr32.html

LM,
Then why pray tell did Stoner himself design the Stoner 63 with a piston set up for the LMG configuration?

Yes, the entire bolt carrier group probably needs to be redesigned for a select fire replacement (or even just a replacement upper).

DI weapons are fantastic when fielded with significant logistical support and when utlised in maneuver warfare. However, they tend to not work as well in static battle (e.g. static defense).

The dust issue is a problem with any weapon system that has close enough tolerances to be highly accurate. Even the renowned FAL had trouble with the dust in the middle east.

Gregg:

Ah, the Stoner 63. Now THAT'S a weapon system. My dream gun. If I only had $100,000 or so to buy a complete transferable set up.

Static defense, you say? Frankly, I'm not sure the water cooled 1917 Browning has ever been topped for that.

Or we could just throw rocks to increase our effectiveness.

If memory serves correct, the 1917 Browning is recoil operated. Thus, how does it fit in this conversation. Particularly since recoil operated weapons that are man portable (as in one man) tend to be small caliber (pistol type) and thus short ranged. And since one other trend in this discussion is accuracy over distance verses the other guys weapon we seem to be loosing the original point of discussion.

By the way, M1As rule even if they are a little heavy.

The late Chuck Karwan once published an article comparing the world's modern infantry "assault" rifles. He concluded that the M16 was best by a nose, mainly on ergonomics. He put the H&K second, and would have put it first if it were a bit handier. There's nothing about the roller-delayed blowback action which demands clunky ergonomics (such as the H&K's left-hand charging lever) so perhaps someone should build an "ultimate rifle" with the H&K action but more comfortable controls-- in a smaller caliber than 7.62x54, of course, which would save a lot of weight compared to a G3.

Zorkmid

Did you see my post re the PTR 32 it is an H&K in 762x39

Anonymous:

We shifted to talking static defense weapons - irrespective of operating system. And static defense means whether it is "man portable" or not is mostly irrelevant.

"Static: not moving or progressing; at rest, not in motion; inactive; stationary."