Max Heat
Well-Known Member
I'm just curious what the "starting" numbers are. It seems that, the more there is, the faster it will grow (by means of wearing down the lands).
For the 7rums I had it was over .4" freebore. The one I gave back with a loose chamber was just over 4" to the lands, and the one that shot well was an even 4.1" to the lands with a sierra bullet; so .4" and .5" freebore.I just wanted to add that after doing a site search, I found information stating that the 7 has about double the freebore that the 300 has. That ALREADY sounds like a bad starting point, for throat life on the 7. But I did come up with some conflicting numbers for the 7. One of them is .220, and the other is .400 (wow). Which one is correct?