The barrel segment is off to METL this am.

Possibly a gunsmith could comment: Is there some device (pilot, mandrel, dent raiser) that could be expanded with such force as to cause the 2 annular furrows? Thank you.

I ask because of this: A 16g victim of chamber lengthening with four 1/4"-3/8" circumferential bulges, with a surface crack.



corresponding to four end of the forcing cone dents; which I presume to be from the reamer pilot?


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