A while back i purchased breech plug & adapters from Precision Rifle. They worked good. My first surprise was how little blow by there was around the adapters. . My second surprise was how clean large rifle magnum primers burn compared to shotgun primers. My third surprise was how the rifle primers don't erode the flash hole. After many shots there started being more and more blow by around the primer adapters. This didn't surprise me. This same thing always happened to me whilst using shotgun primers. To this day, it still surprises me how the rifle magnum primers do not erode the flash hole. Compared to the rifle primers, shotgun primers seem to be mini sandblasters.

After the breech plug started leaking a bit of soot around the primer, i started thinking about the possibility of using an o-ring. Looking around, i found an o-ring i thought might work. It is 1.5mm thick with a 4.5mm ID, which makes an OD of 7.5mm. Some of these o-ring were ordered, along with a 7mm end mill. One thing i wondered, is if the flash hole of the breech plug didn't erode, because of the material it was made from. So.. i decided to modify an OEM Omega breech plug to use the PR adapters. This involved enlarging the flash hole from 0.029" to 0.032", because this is how the PR breech plug came. When the end mill, and the o-rings arrived, i used the mill to enlarge the primer socket in the Omega plug to utilize the PR adapters, and the o-rings.

Now, after two hundred shots, i 'know' shotgun primers are very very much like a sand blaster. My 'homemade' breech plug now has 207 shots through, and the flash hole which was made by a 0.032" drill, now measures 0.032". Large rifle magnum primers are so very very much 'gentler' on breech plugs. Had i been shooting shotgun primers in this breech plug, the flash hole now would be in the neighborhood of 0.037", or thereabouts.

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.

Ive been thinking about trying the one for a Savage MLII. Even if its just for more primer options. I really like that a LRMP is made for 50Kpsi+ vs sub 20kpsi for a 209 primer.

Its funny though, my NULA plug accumulates very little carbon and they last for thousands of shots. Its my belief its because the 209 primer is totally encased in the NULA and tolerances are so tight. Even the primer rim sets into the bolt a small amount.

I have not shot thousands of shots through mine but it shows no wear after a couple hundred. My Savage on the other hand can eat a vent liner in well under 20 shots with hot loads.