T***, headspacing aside, bullet set back can occur with straight wall cases just as easily as bottlenecks!
If I am lucky enough to get a 10mm case necked down to 223, I plan on roll crimping in the cannelure as I do in my AR. (no bullet set back their)
IMHO, a headspace on the shoulder is better, irrespective of this, I would love to shoot 223 points out of my G20 without a barrel change, so you go T***, you make those sabots happen.
Guns don't raise criminals, mommies do!