If I had a .257 caliber barrel, what would be the minimum a person could rebore to, and still clear away all the old rifling/lands/grooves, etc?

Thanks,

Coot

270 is(or was) a common rebore for shot out 25-06's, though maybe 264 might work but then you'd have to work on the action too.

A couple reborers I've talked to usually said they would rebore a minimum of 2 calibers bigger than the original bore.

I think you'd have to go to at least .277" to clean up a barrel with a .257" groove diameter. A ,264" has a land diameter of .256" or so, so a .257" is already .001" larger than that.