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jstyer
02-26-2012, 10:02 AM
Hey folks,

I recently put together a 14.5" middy rifle and it's been loads of fun. I've cycled 840 rounds of M855 through it and it's been flawless.

The other day I was taking a new shooter out and he wanted to try my AR why we were there. I was out of brass cased ammo and had some 62gr wolf HP lying around that I tossed in. I'd never shot this ammo through the gun before and was worried that the midlength system on a 14" barrel might not cycle the lower powered wolf rounds.

I loaded up a magazine for the new shooter and let him have at it. The first round ejected, but short stroked and did not load a second round. I re-charged the gun for him, and his next two rounds were both FTE. This led me to think, "well I guess the gun doesn't like steel".

However, just for kicks I inserted the remainder of the magazine (27 rounds) and tried to fire it myself. I went through all 27 without a hiccup. I loaded one more full magazine of steel and tried again. Once again, all thirty rounds no problem. Thinking it was just an issue with those first couple rounds, I let the new shooter try the gun again. Once again immediately he started having malfunctions. I don't think the rifle went through a full cycle of the action once.

So I ask you all this: Is it possible that this new shooter was soft shouldering the rifle and not giving the gun a good surface to operate against? Because in this instance the malfunctions stopped as soon as a shooter with a good forward leaning stance operated the gun. I look forward to testing this some more the next time I get to go shoot some rifles.

Any thoughts? Is "limp shouldering" real?

p.s Don't worry about the new guy. I paid for some ridiculously overpriced range ammo so he could get his Rambo on. Also, did you know that on a Motorola 'Rambo' is auto corrected to tambourine?

p.p.s. I had no idea going into it that this post was going to be so long. So apologies for that. But I paid the price, my thumbs are killing me!

(Sent from tapatalk)

Kyle Reese
02-26-2012, 10:48 AM
It's certainly possible, but also bear in mind that most of the .223 imported steel cased ammunition (Wolf, WPA, Silver Bear, Brown Bear, etc) is pretty inconsistent in terms of quality. I've shot it off and on since about 1999 in a variety of carbines with varying degrees of success.

I wouldn't worry about it if your carbine cycles/functions properly with M193 / M855 / Duty type ammunition.

You mentioned that you put together a 14.5" middy.

Was this carbine assembled by you 100% (important to know), or did you buy a complete upper?

You can also ensure the new shooter employs a proper shooting stance. :)

jstyer
02-26-2012, 11:07 AM
So far it's been 100% with duty ammo. I have about 300 rounds of wolf left from a 2000 round batch I bought a couple years ago. And I'm slowly burning through it.

And it was touch and go with the shooting stance... if I thought he had even the slightest interest in actually shooting firearms, I would have got the 22 and we would've actually worked on it.

This was a 100% build by me. I used a DD 14.5" mid-length lightweight barrel, a DD modular quad rail, and a spikes upper receiver.

shootist26
02-27-2012, 10:37 AM
before I sold my old bushmaster carbine, I would occasionally experience this problem as well. Happened when shooting steel case off a bench and the stock was held limply against my shoulder. The round would only partially chamber. It functioned fine whenever I fired it from a normal practical position since the stock was more firmly shouldered.

At first I was at a loss since I had eliminated magazine and lube related root causes.

JRas
02-27-2012, 12:04 PM
"These 14.5" mid length gas barreled upper receiver groups have been specifically tuned to be a very soft and fast shooting set up. They are a joy to shoot, but please feed it good ammo. With good milspec pressured ammo we have been running H buffers. We do not recommend using lower powered ammo. If using less than milspec pressured ammo, it may be best to run a standard carbine buffer."

quoted from BCM

jstyer
02-27-2012, 01:00 PM
We're drifting a bit here...

As mentioned in the original post, I'm very familiar with the mechanics/limitations of the 14.5" mid-length system. I even mentioned that I thought the rifle would not function at all with the lower pressured steel cased ammo. If I was taking a class/hunting/using the gun in a defense type roll I would obviously only be using quality brass cased ammo.

However, the same gun on the same day using the same ammo, was 100% reliable with one shooter and about 5% reliable with another. I'm curious as to whether you guys think giving the gun a weak shoulder could potentially cause a malfunction, in the same manner that a weak wrist could induce a malfunction in a pistol.

rob_s
02-27-2012, 01:26 PM
Anything is possible, but I will tell you that I've fired ARs multiple times for one reason or another with no rearward resistance to the gun (sitting on a rest un-impeded) and not had malfunctions.

Depending on the age of your Wolf, it still could be the ammo just with a coincidence that it happened to him and not you. While all the import steel ammo is known for inconsistency, the 2009-2011 pre-WPA Wolf is all even MORE suspect IME.

You were there though, did it look like the shooter was going anything wrong? If so, did you correct him?

jstyer
02-27-2012, 07:22 PM
The wolf is from 2009... so it very well could've been the rounds. I did correct him with his stance, but by then we were shooting brass stuff. So no malfunctions there.

I'm going to take some of that wolf out next weekend and see if I can replicate it. Thanks for all the participation folks. Since no one seems to have ever experienced a malfunction due to shooting stance with a rifle, I'm going to chalk this one up to ammo.

Failure2Stop
02-28-2012, 07:39 AM
I have fired ARs from the "Palestinian Support Position" on numerous occasions and had no issues with M855.