Quote Originally Posted by CPM View Post
Does FTF in the context you used it mean failure to feed or failure to fire with the small indent in the primer you wrote about? I have seen countless SPR builds with super light triggers cause this. If you are referring to a failure to fire I’d be interested in what a standard hammer spring does.

What trigger are you using?
Quote Originally Posted by ViniVidivici View Post
I've seen an out of spec cam pin drag inside an upper, the square head was literally too wide. Might be worth looking at and measuring.
The bolt would hang up about a half inch from seating fully. Then ,when fully closed, would get a light strike. Im ruling out the trigger, as it is a drop in Velocity 3lb, and it is hitting plenty hard. Ive got two of these btw, one a 4lb, they are built like tanks % excellent.

Vin..thank you. Ive got calipers..whats the spec on that? I did not see any drag or wear as I can now recall, but Ill check this if I can get the spec.