My oil burning pig. Pics too!

AJ/FormS said

nm9
What am I missing? .3125 rounds to .313, being shorthand for the missing .0005

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Yeah....I just wanted to know where that number came from.....just in case something is not quite right. An actual .313 spec?.... 'made to fit 5/16" '?....measured in some fashion?.... converted from 8mm?