As I said, .005 run out, won't hurt anything, you could even chuck it in the jaws and leave enough, forward of the jaws, for tool clearance. The case head that you will be chucking on, is solid brass. And if your worried about the run out, turn the rim a extra .003 to compensate for the run out in the bolt face.

For the rim thickness, put a center hole in a piece or 5/16 stock, that's a little longer than the inside of the case. After you turn the rims. Use a 5/8 or larger piece of stock and bore a pocket to the depth you want the thickness to be. Put the 5/16 piece in the case and push it against the pocket and thin the rims. It will hold like a clutch. 

You can also cure the rim diameter problem, by stripping the bolt and turning the bolt face to .505 and deepen it to accommodate the 30/30 rim.

Wouldn't be nice to use the 30/30 cases w/o working on them.