So, case stuck in '06 sizing die.
I made up some load testing rounds using my 308 die for neck sizing, wondering if anyone knows a reason I shouldn't've.
The 308 is bigger at the shoulder, with a slightly larger radius on the shuolder (20deg vs 17.5?) but the rounds chamber fine.
So unless someone shouts me down, I'm taking them out.

If you keep up practices like that sooner or later you will hurt your self, hope no one else is around when it happens. Do you put in different spark plugs in your cars engine also.

I said neck-sizing, but I actually sized down the shoulder.
It's only 50 pieces of brass, and I could always just fireform them, but if there's no problem I'd rather not hassle/waste bullets.
Well, the bolt does lock down, but I'm thinking if the 308 has a larger radius, and I'm running the brass down the length of the shoulder (to the bolt-side of the shoulder) then I'm in effect creating more headspace.
(Leaving the base of the shoulder put, then increasing the radius brings the top of the shoulder "down" toward the rim.)
From adding celophane tape on the rim of a case until the bolt meets resistance, I conclude that there is a bout .007" play between brass and chamber.
Can't find the SAAMI tolerances on the web.

Found it.
Looks like .01", so I'm going with it.

BTW, Reload, I'll be by myself, so no worries there. The range I go to only allows commercial ammo, so I shoot reloads in the woods.
As for the car, don't drive. Too dangerous!