Never had much luck with McGowen.
First off, that primer looks pretty flat(high pressure). Maybe it just looks that way in the photo though? Are you experiencing a sticky bolt when you cycle the bolt after firing a round? What powder, charge and bullet are you using?
Did you remove the extractor and ejector and use go/no-go gauges when you headspaced the barrel? Are you noticing any change to the shoulders? How about overall length before and after? Did you remove the extractor and ejector and use go/no-go gauges when you headspaced the barrel?
Bookmarks