I have a Rock River Arms upper that I have been running Federam XM193 5.56 and American Eagle .223 out of. The shoulders of the spent brass appear slightly buldged forward, toward the case mouth. The neck is not buldged, just the sholders, and it is slight.
The bolt appears to close fully with a cartridge in the chamber, and the cartridge seats fully in the chanmber
Is the buldging normal?