As mentioned... Measuring factory, then firing shows measured .009 ish. My loads loaded to same or slight less... It is what it is. Vel is 2350 ish so not crazy. Factory was just about 2300.that's quite a bit of CHE.
like 5-6 is more recommended number.
only problem is I could never get 100% behind the CHE thing, since the cases could be any diameter going in.
if they were bigger than the chamber they'd either never come out or you'd be expanding the steel.