I need some guidance here.
The problem: my gun has started to fail to feed. It was shooting just fine but then started to experience failures to feed after every shot. Since the failures started I've noticed that it also has had 2 failures to eject and 3 failures to close the bolt in the last 50 rounds.
The ammo: All hornady red box 77r OTM. The gun has only had this ammo put through it, and only about 500 rounds total. It has been fed with Magpul and Lancer 20 round mags.
The rifle: BCM 410SS 20" Service profile barrel with BCM BCG. Rainier Ultramatch upper receiver with rainier "match" gas block assembled by Rainier. Gas block has a set screw (barrel comes dimpled for set screw). The issue has occurred on two lowers: one with rifle gas using rifle buffer, the other with the Vltor A5 system.
Shooting prone the brass ends up around 4 o'clock 4 feet away. The gas rings look good, i switched buffer springs, and tried different mags. What else can I do to try and diagnose?
Thanks,
-LOP

