When the aluminum shim in the Omega breech plug failed a few day ago, it was seen that there wasn't enough primer seat left to repair, so a grade 8 bolt was installed to bring material to work on. This i was able to do because of the information and advice given by Screwbolts. When the aluminum shim in the Accura breech plug failed, it turned out there was enough material left in the primer seat to modify the breech plug to use 0-ring.

Previously i had tried rubber 0-ring, and experienced some grief trying to make it work. Part of the rubber was blown into the flash channel, by the primer, and plugged the flash hole, so i gave up the idea of o-ring. Busta posted and explained there was too much compression on the o-ring, and this along with the taper in the primer seat was why i had problems.

In the days since, i ordered some silicon o-ring, and when the Accura started belching blow back, i decided to give them a try. So, what i did was grind a C drill more flatter.










This flatter drill was used to drill into the primer seat of the Accura breech plug about 0.050". This allows for the o-ring without overly compressing it, and results in a nice nearly flat primer seat. Here is the modified plug next to a 'new' factory plug.











The other end of the breech plugs showing the vent liner from Precision Rifle installed in the modified plug.











The breech plugs with the silicon o-ring installed. The headspace with the o-ring installed was 0.020" less than factory. This results in a nice tight seal between the primer and the o-ring, without too much compression, which results in zero blow back.









Here is what the spent primers from the Accura look like, with the nice tight seal, provided by the o-ring.










Here is a picture of the o-rings. A new rubber ring, and a used rubber ring. A new silicon ring, a silicon ring that has seen 4 shots, and a silicon ring that has seen about 25 shots. The ring with 25 shots on it, is installed in the rifle right now, has 29 shots through it, and is still viable.









Busta' experience and advice regarding o-ring, seemingly has allowed for success. It is actually quite simple to modify a breech plug to accept an o-ring. One needs a C drill, and patience. Approaching the correct depth of drill needs be done with care. Flattening a drill also seems to be a good step, but probably isn't absolutely necessary.