Most manufacturers punch the primer pocket into cartridge case head.
Therefore all cases do not have equally deep primer pockets, and the bottom usually has a radius. This causes the primers to be seated unevenly and to different depths.
It could cause some primers to protrude from the rear of the case, which is dangerous because it could cause a slam fire
Primers should be seated to 4 Thou, or 0.1mm, below the surface of the case head.
For safety and uniform ignition it is strongly advised that the primer pockets be cut to the same depth.
This is done with the MAMBA primer pocket uniformer.
