im not exactly sure where to put this but here seemed like a good starting point. I recently traded a couple 200$ shotguns for a .300 AAC Blackout that a guy built for his girlfriend who he broke up with because she had drug problems anyways I was sighting my scope in and i could fire a round but the bolt wouldn't move(no ejection) my father in-law was helping me and he said he could see gas coming out in front of the bolt carrier, so that would lead me to believe the gas black is lined up correctly on the barrel and the head spacing seems to be correct because everything sits flush like it should. So does this mean the gas tube and the gas chamber on the bolt carrier aren't seating correctly or what? any suggestions or thoughts would be great. Also ive talked to the guy and he said if i wanted to bring it over he could look at it but i want some second opinions first.