Hey guys - I'm troubleshooting a rifle for a family member. It's a DPMS AR-15 and it's not working properly after some rapid fire sessions he had with his son. The rifle will pick up a cartridge from the magazine (via charging handle and release lever) but often won't grab the next cartridge after successfully ejecting the spent casing. I see a slight marring on the casing that is ejected, not sure what information can come from that, but I've attached it. Today while testing I noticed when it didn't pickup the next round the forward assist could be used to move the BCG up another 1/8th inch. But still didn't fire as it didn't grab another round from the cartridge. I also noticed it not locking back on the last round.
So, here's what I've tried - I cleaned and oiled the buffer tube spring, ensuring it was properly torqued back down. I cleaned and lubricated the BCG at a field strip level. I tightened the magazine release by one turn. I've tried 6 different magazines from 4 different manufacturers. Including known working new PMAGs I use in my other rifles.
What else can I try before bringing it to a gunsmith?
Any help would be sincerely appreciated, I'm a noob with ARs.
So, here's what I've tried - I cleaned and oiled the buffer tube spring, ensuring it was properly torqued back down. I cleaned and lubricated the BCG at a field strip level. I tightened the magazine release by one turn. I've tried 6 different magazines from 4 different manufacturers. Including known working new PMAGs I use in my other rifles.
What else can I try before bringing it to a gunsmith?
Any help would be sincerely appreciated, I'm a noob with ARs.