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VaniB
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Posted: 9/25/2009 4:23:06 PM
[Last Edit: 9/25/2009 5:49:29 PM by VaniB]
I took the A2 fixed buttstock off of my 24" LR DPMS 308 and installed a heavy duty slash carbine buffer and spring with an LMT collapsible butt stock. I stuffed 4 handloads into the 20 round magazine, and feeding was fine but I experienced a "stovepipe" style ejection with the second round. The 308 case got caught-up and sandwhiched between the bolt face and front chamber wall on the way out.

I had these handloads loaded with 150 grain speer bullets at about 100 FPS below maximum. ( still fairly stout in the Hornady listings and in the column just right before the max listed load) My other two rounds chambered and fired fine.


Can the buffer change-out be responsible for this?.....or, was it the 150grain reloads maybe being too light?..... or is it just that crap happens every so often and don't worry about it?

I'm about to install a new 18.5" barrel and don't want to build on top of prexisting problems.
LastRites
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Posted: 9/25/2009 5:41:18 PM
Could be a fluke, but for one to base a fatal flaw on only 4 rounds after a component change isn't right. You gotta really test drive that thing a little more.
Gamma762
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Posted: 9/25/2009 5:43:27 PM
[Last Edit: 9/25/2009 5:44:18 PM by Gamma762]
Stovepipe can be either too much power/cycling too fast, OR too little power and not cycling fully. Or just a problem with the ejector... spring weak, damaged, or fouling causing it to stick.

In your case, if you didn't make any changes to the upper and you're using reasonably hot loads, very good chance that the cycle speed of the action is too fast and the case isn't getting out of the action fast enough before the bolt closes on it. You need to retard the cycle speed, which could include reducing the amount of gas, using a longer gas system length to change the timing, a heavier buffer to slow opening of the action, or a buffer that absorbs energy at the end of the action cycle as it hits the back of the buffer tube.

Originally Posted By LastRites:
Could be a fluke, but for one to base a fatal flaw on only 4 rounds after a component change isn't right. You gotta really test drive that thing a little more.

Agree that 4 rounds isn't a very extensive test.
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jaqufrost
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Posted: 9/25/2009 5:44:33 PM
[Last Edit: 9/25/2009 5:46:01 PM by jaqufrost]
Most stopepipes I've seen come from the shell bouncing back into the action off of another object. Normally hands or walls.

ETA: was the base of the bullet or the neck of the bullet stuck in the action?
VaniB
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Posted: 9/25/2009 6:03:55 PM
[Last Edit: 9/25/2009 6:05:02 PM by VaniB]
It was the opening/case mouth coming out first, and like I was looking into an open "stove-pipe".

Funny though you should say that about it bouncing back off of something; I have always kept a cloth draped over the ejection port to prevent empties from flying into the next county. This is the first time out of perhaps a 100 rounds that I have fired out of my rifle, that the case would have been deflected by a limp cotton pillow-case cloth, and was sent right back into the chamber.

It just makes me suspicious that this is the first ejection event I had experienced......right after installing the slash buffer and spring. I don't know jack about buffers and springs and can only presume that slash is very knowlegable about these parts and that he sold me what is supposed to convert the fixed stock to an LMT collapsible stock.....reliably.