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Unread 09-12-2014, 09:54 PM   #8
sheepherder
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Quote:
Originally Posted by ithacaartist View Post
Rich, thanks for tightening up the math--I did the subtraction and did an estimate of the half. Theoretically, it would be a bit less if you're measuring the bottoms of the grooves.
You are right - I used John Sabato's dimensions. D'OH!!!

I get ..299" [7.6mm] for my 'insert diameter' (actual measurement). And with .224" bullet diameter [bottom of groove], that gives .037" wall thickness for the 30 cal insert.

Paper clip thickness.

BTW: Here's a pic of the 9mm/.22LR conversion 'kit' that I dug up somewhere, showing all parts.
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