Quote Originally Posted by Parashooter View Post
Swissicon Berdan primer diameter: .217"
Large Rifle Boxer primer diameter: .210"
Difference: .007"
Thickness of material required to reduce diameter by .007" = .0035"
Average human hair thickness: .004"

Here is another approach -

https://www.milsurps.com/images/impo.../33zbjwn-1.jpg
I hadn't ever measured, my guess was way off seems.

Can you go into detail on step 3 a little. I'm trying to figure out how you went about shrinking the primer pocket.