6mm ARC

[kmon]

A5 and Greyfox, I am quite sure you could do that, but if I were doing it the bullet would be jammed into the lands to hold the base against the bolt face. I know even on some AI variants for fireforming that is recommended for improved brass life of the fireformed brass. Essentially in that case you are headspacing in you chamber off the bullet not the case.

But your brass would wind up being short in the neck. Doubt that would be an issue but would be the result.