I never do anything other than mount the can, then do a couple quick checks on ARs.
1. Remove the BCG and look down the barrel from the receiver end. Does it look like a round circle?
2. Shine a light into the receiver end of the barrel. Does it put a perfect circle of light on the wall?
If you answer yet to both of those, send it.
You can do a similar thing with bolt guns by removing the bolt. Got a couple levers and a pump that I just installed the can and pulled the trigger. Don’t think I’ve ever checked a pistol before shooting, but you could remove the barrel (if that’s an option) and attach the can to the loose barrel and do the same checks.