head space issue 300 aac

[KYregular]

For all who say no need to check headspace on an AR, heres what I just ran into. Bought a 16" 300 blackout barrel from ballistic advantage to replace my 10.5" ballistic advantage with. went to check headspace and right off the bat would not close on the go gauge. details
foster go no go gauges
toolcraft bcg (same one I used on 10.5")
ejector and extractor removed to test
bolt and bolt pin checked before test
bolt closes on empty chamber but not with the go gauge inserted
looks to me like go gauge is sticking out pretty proud of the chamber
email sent to BA
any advice?

 

[nastynatesfish]

Did you clean it before trying the headspace guage? I’ve personally never checked headspace on an ar. I’ve never had an issue

 

[bangswitch]

Call the barrel maker for return authorization, and send them the bolt you plan to use. Have them re-ream the chamber and match the bolt to the barrel. It's easier from the get-go to buy a matched bolt when you buy a barrel, then no headspace issues. The new bolt should fit the carrier with no issues if everything is milspec.

 

[jmorris]

I would probably fix the rifle so it would work with factory ammunition but if you only have one and plan to load for it you might be able to make your brass fit. Start moving your size die “up” and come down in small increments until the bolt carrier will close and the case can be easily extracted. Case gauges will be less useful also but it could get you going.