Well, I don't know what they did that may have solved the lock-back issue as well as the failure to extract/eject but the bolt locked back on empty on every mag that I emptied.
The repair tag doesn't mention the spring or gas block, not sure if they did anything else that would have fixed that...
Final update:
Went to the range today and tested the gun out and I'm VERY happy to say, it works perfectly now! 100% through about 75 rounds. I couldn't get 3 rounds without a jam before.
It's actually a pleasure to shoot knowing that every time I squeeze the trigger a nice loud bang is heard...
Got my LAR-308 back today!! Not terrible turnarond time and they paid for shipping and warranty work.
So, it says replaced ejector spring, extractor upgrade, polished chamber and checked headspace.
I'll have to get to the range and test it out but I'm feeling good!
They beat the 3 week...
Well, I sent it off to DPMS today, UPS came by with a shipping label and everything. So far, my experience with their customer service is VERY good! Don't worry, I'll update everyone as this progresses. I'm expecting something in about 3 weeks, just keeping my hopes up :)
Ok, it looks like this is a recommended fix:
http://www.midwayusa.com/product/663270/dpms-extractor-and-spring-upgrade-assembly-lr-308-gii-matte
Unless someone says otherwise, I'm going to give it a shot (pun).
Ok, I took it out again to test the lube theory... the BCG was almost dripping by the time I kept adding lube to it. It seemed to help the full cycle of the bolt, I could get it to lock back more reliably (still not 100% though) on a single shell in the mag. But... the gun still jammed.
It...
A couple of the cases were dented from the bolt jamming it against the round that was not ejected. None of the rims had any weird markings on them where it may be too difficult to extract. The ones that didn't even extract from the chamber were easy enough to get out, just dropped the mag...
The bolt does not lock back reliably. That's why I am thinking it is undergassed.
The gun has never been reliable. I've focused my attention on the bolt because I thought it was stiff. It's been soaked and cleaned a few times. It has a good coating of remoil throughout. It's almost as if...
Yeah, probably that gas too but in this case, I'm referring to my LAR-308. It's an internally stock factory DPMS.
Yesterday, I was able to get through a 20 round mag with no problems but after that, with the same rounds, I couldn't get 3 in a row off. Some were stove pipes, some were FTF...
I think you are a master. To say I'm impressed would be an understatement! Incredible craftsmanship and handwork! I thank you for posting it so we could follow and learn from you!
Wow, what an awesome build and great thread to walk us through! Thank you so much for the detailed explanation and pictures of this wonderful recreation!