Wanting to get involved in double guns I picked up a very nice 615A 12 gauge made in 1950. I had a reputable MN gun smith open up the chokes (Skeet II & IM)and lengthen the chambers so I could shoot low pressure 1.25 ITX loads. After making numerous test loads I found the gun will not pattern with ITX. In fact the patterns are so bad a friend of mine commented 'where did the shot go' as most was not on the paper at 25 yards. I did find the gun will pattern reasonably well with straight loads (no shot cup) I measured the bore and could believe it measured .719 - in fact I machined a Gilchrist brass bore bushing to double check and confirmed a .718 bushing is snug but will travel the length of the bore. In retrospect I should have bought a higher grade gun but I what to keep this project going.
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Given the bore size I thought I would lengthen the forcing cone and open the chokes up to cyl and Imp cyl - OR - do I give up on this one and keep it for lead shot only??
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Your thought are appreciated and I purposely left some grammar items for Bob to comment on ....... Thanks
