Bought a Polish AKM kit from AK-builder with the new barrel already populated and headspaced. Took it out last night, took the firing pin out of the bolt and threw a NO-Go gauge in, didn't close up. Put a GO gauge in, didn't fully lock. Put it in the bolt carrier, same results. Put some live rounds in, about 9/10 of them closed. I'm hoping they weren't in a rush to ship and drilled my barrel wrong before shipping. Does this sound like it might be a problem when building?