Why? This may be next
16g No. 0 L.C. Smith with chamber lengthened to 2 7/8"



Radiograph with the bulge and thin wall



or even worse, courtesy of Randy McCune; chamber also inexpertly lengthened to 2 7/8" and forcing cone lengthened. I don't unfortunately have the end-of-chamber wall thickness and the reload also showed evidence of over-pressure



Briley's same gauge chamber sleeving is $275
http://www.brileygunsmithing.com/c-879-full-list-of-shotgun-gunsmithing-pricing.aspx

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