Kbb; you're ok from a safety standpoint if the bolt won't close on the go-gage, but will close on factory brass. I have checked chambers that would not close on a go-gage, but would on factory brass. On a .458 Win Mag, I would go about .002"-.003" over the go gage. The belted cartridges are very hard to close (and may not), if the belt on the cartridge makes up on the chamber headspace face too early. Not good on a dangerous game rifle where you really want a round to chamber smoothly every time.
Just my opinion, Tom
Texas State Rifle Association Life Member
NRA Endowment Life Member
A big fast bullet will beat a little fast bullet every time
Last edited by specweldtom; 08-20-2008 at 10:37 PM.