Help: My DPMS LR-308B jams and misfires

[Retro]

I got my new DPMS LR-308 two week and I ran about 200 rounds through it, although the accuracy was superb, I have been having a lot of mechanical problems with it. I have 3 steel DPMS 10 rd magazine (the new ones from 44mag.com, not the C-mags).

1 First: every 3 rounds or so, it will not chamber the next round, and every 3 or 4 rounds, it will jam with a round stuck half way between the chamber and the magazine because the bolt fails to catch the bottom of the shell case. I tried multiple ammos with similar results. The bolt is well-lubed, and I hand cycled the bolt 100 times, and so the problem is not because the rifle is new, and I am not using the problematic C-Mags but the new DPMS steel mags.

2. Second: using British NATO surplus 7.62 rounds, it will always misfire the second round. I inspected the dent on the misfired primer, it was as deep as the spent shells. But if I locked the bolt back and chambered a round by pressing the bolt release bottom, that round will go "bang", but the next round will load and then "click" ... misfire...

So my question is where can I get an enhanced hammer spring for DPMS LR-308. Wolff springs does not have it.

Advice will be appreciated.

R.

 

[Cap'n Jack Burntbeard]

This almost sounds like an improper feed, did you inspect the feed lips on the mag?
If the casing hangs up during the feed cycle it could cause problems, I have heard of this happening on new FAL mags, but since DPMS uses their own mags this may not be the issue.
At any rate I hope you can find a solution, since there's nothing worse than an expensive gun that goes click instead of bang.

 

[wally]

If they are DPMS OEM mags I'd contact DPMS about the problem.

If not, how does the magazine that came with the gun function?

--wally.

 

[Karl Hungus]

I'm with the Cap'n. Sand/buff the lips of the mags. I've had to do this with all my DPMS mags. Can't help with the second problem - I built up a SASSy Lr-.308 last winter and have about 800 rounds through it so far - no missfires.

 

[Retro]

Should I sand/buff the outside of the lips, or the inside of the lips?

I ordered some C-Product mags just to see how it would function since the DPMS factory ones are faulty. I ordered an extra-power hammer spring for AR15 hoping to solve the second problem...

Thx

 

[briansmithwins]

Since you bought the rifle new and it failed with several different mags and ammo I'd send it back.

Rifles should work without having to replace parts. BSW

 

[wally]

I ordered some C-Product mags just to see how it would function since the DPMS factory ones are faulty

Good luck with that. The five I got from C-Products last month (after a three month wait!) wouldn't even let the bolt close -- the feed lips were wrong!

--wally.

 

[yehork]

Please contact Shane in Repairs at 1-800-578-3767. It sounds like there may be a number of factors contributing to the problem, but I'm leaning toward an issue with the magazines causing most of it. He'll have a few questions for you and if it is the mags, he'll have you send them in and we will replace them if they are found to be faulty.

 

[Retro]

Update:

I ordered 2 C-Product Magazines, and I took out the DPMS magazine springs and I stretched them out a little and reinstalled them to increase the spring tension. I took the rifle and 4 mags to the range. Fired 3 rounds through each of the DPMS magazines, jams and misfires and bents as usually. Then I loaded the C-Product Magazines, fired 10 rds in each magazine without a single malfunction.

Conclusion: All 4 DPMS magazines are defective. Rifle works perfectly with C-Product Mags.

 

[lipadj46]

If you bought them from 44mag.com give them a call they will replace them I bet.

 

[Retro]

Yeah, I did. But it doesn't matter, man... none of the DPMS mags would work in my DPMS rifle... giving me new ones won't help. I examined the C-Product mag vs. DPMS, C-Product has a much higher feeding lip than DPMS mags.

 

[lipadj46]

Get some other mags then, you have an AR15 right? Get some pmags or something, better than paper weights.

 

[jpwilly]

My C-Mags work fine in my LR-308 aside from being a little snug in the mag well. DPMS must be cranking the new LR-308's out too quickly now to catch up before the orders go away. I sure hope they get these issues fixed before too many people have issues! I have 3 DPMS rifles and they all work great!