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Gunsmithing Does this look right?

cast1

Polyhobbyism sufferer
Full Member
Minuteman
Nov 23, 2011
795
1,374
From what I can tell it looks like I've cut a good chamber here. This is the first time I've direct indicated, drilled and prebored. If this rifle shoots this is how I'll be doing it from now on.

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Looks like you have a .0035" ding or divot (possibly a stuck chip, not likely a land that far back.....). You've probably long since removed the barrel from your lathe, but I would have moved the indicator back and looked for a smooth spot. Until the barrel comes around to where the indicator takes a dive in the pot hole, it looked like it was running about .0005" variation.

If you dialed the barrel in with rods, you should have been able to get to about .0002 or .0003" on each end. Under those conditions, I would expect to see .0005 to .001 variation in the chamber like you were measuring.