Currently the shot count through the rifle primer breech plug is 277. The flash hole now measures 0.032". The flash hole was made by a 0.032" drill.

A while back Busta sent me a couple stainless vent liner to test.

http://www.huntingnet.com/forum/blac...ent-liner.html

Using W209 primer, the flash hole of one of them vent liner grew from 0.028" to 0.035" in the exact same 277 shots.

The deposits in the breech plug fire channel builds a way faster with shotgun primers, and it is a way harder. Another noticeable happening, is the flash hole when using shotgun primers never gets plugged, and it never gets smaller; it just grows larger. When using rifle primers, the flash hole gets kinda smaller. The 0.032" gage doesn't want to go through a dirty flash hole. Normally what i have to do is use a 0.031" gage first..then the 0.032" gage can go through the flash hole. A 0.033" gage is a total no go.