DPMS LR-308 Problem

[vbfisher]

Saw a few other posts on here, but problem may be a bit different for my rifle. LR-308 feeds fine for the first 15-18 rounds of sustained fire (30-60 seconds of firing). After that it efects spent brass but does not feed the next round. Same for each round after regardless of number of rounds in the mag (full vs mostly empty). Cycle charging handle, and fires fine, with same result. If I let the weapon sit and cool - seems to do a bit better. Any thoughts ? I've completely disassmebled and cleaned the weapon - no luck.

 

[vbfisher]

Re: DPMS LR-308 Problem

Using factory supplied mags

 

[elfster1234]

Re: DPMS LR-308 Problem

magpul 20lr magazine

 

[BCP]

Re: DPMS LR-308 Problem

Does the bolt stay open after the last round in the magazine is fired?

Trying different ammunition and magazines would help too.

 

[icarus2005]

Re: DPMS LR-308 Problem

Have you done any mods?
everything factory?
is the gun new?

A feed issue like that is most common one of three things

1. bag magazine. TEST: rather than doing what you have doing, use several mags fully loaded, but only shoot the first 4 or 5 rounds, then quick mag change. if the problem goes away then you know your mags lack spring pressure or have too much wall friction

2. Buffer spring. if the bolt doesn't go back far enough it won't feed the next round. sound unlikely given your particular situation.

3. Filth. how many rounds have been run through the gun? how well has it been cleaned? as the gun heats up things expand, ever so slightly, but that makes everything thighter, meaning for difficult for the bolt pull the round out, perhaps keeping it from going back as far as it should to feed the next round.
TEST: clean teh crap out of your gun and see if that fixes the problem.

thats my poor boy opinion, and you can take it to the bullseye!

 

[BigPoppaHugeTime]

Re: DPMS LR-308 Problem

I had the same problem with my AP4. I polished the chamber because I read a lot of reports stating they were rough. I'm glad I did it, but that wasn't the problem. I thought maybe it was my reloading, so I really paid close attention to my sizing. Still not it. So I went ahead and picked up a couple of pmags to try (wanted them anyway). Problem solved! I can't recall having a feed issue since.

 

[problemchild]

Re: DPMS LR-308 Problem

Almost sounds like they forgot to chrome the chamber area.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: vbfisher</div><div class="ubbcode-body">Saw a few other posts on here, but problem may be a bit different for my rifle. LR-308 feeds fine for the first 15-18 rounds of sustained fire (30-60 seconds of firing). After that it efects spent brass but does not feed the next round. Same for each round after regardless of number of rounds in the mag (full vs mostly empty). Cycle charging handle, and fires fine, with same result. If I let the weapon sit and cool - seems to do a bit better. Any thoughts ? I've completely disassmebled and cleaned the weapon - no luck. </div></div>

 

[BigPoppaHugeTime]

Re: DPMS LR-308 Problem

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: problemchild</div><div class="ubbcode-body">Almost sounds like they forgot to chrome the chamber area.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: vbfisher</div><div class="ubbcode-body">Saw a few other posts on here, but problem may be a bit different for my rifle. LR-308 feeds fine for the first 15-18 rounds of sustained fire (30-60 seconds of firing). After that it efects spent brass but does not feed the next round. Same for each round after regardless of number of rounds in the mag (full vs mostly empty). Cycle charging handle, and fires fine, with same result. If I let the weapon sit and cool - seems to do a bit better. Any thoughts ? I've completely disassmebled and cleaned the weapon - no luck. </div></div> </div></div>

I don't believe the poster stated his barrel was chrome lined, so his chamber wouldn't be either.

 

[WKR]

Re: DPMS LR-308 Problem

Try different ammo, sometimes low quality ammo will cause this, it's happened to me on a .223 BM while using steel case ammo.

 

[moots]

Re: DPMS LR-308 Problem

Try a different mag and only use good ammo

 

[vonfluehaugen]

Re: DPMS LR-308 Problem

I have this identical problem. I have tried multiple brands of magazines (including P-mags), multiple bolt carriers and bolts, multiple barrels (one original factory, and one custom). And multiple brands of ammunition, including some top class Federal. And YES, I have cleaned it like crazy in between tests. But always the same behavior: first clip rocks the casbah, everything after that royally sucks.

 

[ToddKS]

Re: DPMS LR-308 Problem

I had a similar problem with an AR-15. The bolt would come back when fired, but not all the way so it did not strip the next round from the magazine. I finally figured out that my gas block had come slightly loose and moved just enough forward that it was not delivering enough gas to fully cycle.

You might check your gas block and make sure it is tight and in the proper location.

 

[dixiejarhead]

Re: DPMS LR-308 Problem

Gas block is leaking gas. Common problem with DPMS