post up some pictures of the fired cases the striker and the carrier

who built it? whos striker system did they use? there is 4 different striker systems
there is the big spring over the rod (HA). the little spring over the rod. seperate spring for the striker above the recoil spring. pushrod style with internal springs.

with out the recoil springs and striker spring in do all your parts run back and forward(to lockup) by tilting the receiver up and down 45*?
how straight are the slots for the striker and carrier?
is the striker cut to fit onto the back of the carrier or has the back of the carrier been cut away?

it could be
carrier or striker binding in the slots in the receiver if they are not smooth and straight. or it could be the striker wedging into the receiver when the carrier pushes it. or is could be loss of gas, gas bypass on the piston