gman57

Another ring you might want to check out is a 5-193. It is a commercial high pressure - high heat 'O' ring....

If you want a more permanent solution you could install a 'stainless' steel washer in the bottom of the primer pocket. You will have to turn it down to the correct diameter and thickness. One problem might be the thickness... i am not sure what that might be but Ron would know.

Here is one installed in a Knight BP...



I probably have 100 shots on this stainless washer now and it shows no signs of wear - actually it is really hard to tell if the washere is in there or not...

Nice Tip Mike, Im gonna have to see if I can find some of them (Heat-HP-O-Rings). They'll probably last a-lot longer and hold up to the heat much better.
(BP)

The silicone o-ring was purchased from Amazon. My Accura will not close on this o-ring without making the primer pocket deeper. My rifle will close on a metal washer that reduces the head space by 0.016". It will close on a o-ring that reduces head space by 0.020", and does seal and allow no blow back on an o-ring that has decreased the head space 0.015".

sabotloader suggested you might consider a stainless washer. This would work too. However, that involves turning the diameter of the washer down to some less than 1/4", and reducing it's thickness to no more than 0.016" or so, unless you make the primer pocket deeper.

If you have an Accura breech plug that is new, or in good condition, the blow back isn't much..........perhaps not enough to worry about..........not enough to go to any expense, or do a breech plug modification. Myself, i started down this road of breech plug modification, first, because i had a hang fire once in a great time using BH209, and second, because my breech plug suffered from flame cutting in the primer seat. When i think about it, it seems to me that it is possible i had problems with flame cutting on the primer seat, because i didn't keep the breech plug clean. I haven't been too diligent keeping my rifles clean. It is conceivable to me that a clean breech plug won't suffer as much flame cutting.

If you wish to modify your breech plug for the fun of it, i fully understand; i have truly enjoyed playin' around with my breech plugs, and all the new things i have learned, and experienced. Right now i would rather work on breech plugs than do any of the other chores waiting for me; it is fun, and interesting.

with the cci 209m and bh209 in my accura. blow back isnt even there. Just a fine layer of dust that wipes off with a finger. i need to try some rem sts primers, forgot all aboot them.

Thanks for the suggestions guys I modified 2 BPs with vent liners and enlarged fire channels as per earlier posts, just seemed like after like 15 shots or so my breech area was kinda black maybe its the Fusion ML primers I was using have to try some others, but I cant help tinkering with my gear.

Hey guys Ive been trying to find a C size drill bit and people in Home Depot and Lowes never heard of C size. Do you have a metric or inch equivilent? Thanks oops forgot I can just try miking it up later.

http://www.carbidedepot.com/formulas-drillsize.htm

There is a drill size chart. I purchase my drills from a machine shop/machineshop supply business. Perhaps there is such a place where you live.

gman57

These guys are pretty darn helpful - to even the little guys. Even when you are not sure what you are looking for the can direct...

http://www1.mscdirect.com/CGI/NNSRHM

Once again thanks guys

I have a 10ML2 and shoot smokeless in it, and youre exactly right, the higher pressure cause the breech plug hole to get bigger and then you get blow back and finally lack of ignition. They recommend you change the vent liner every 100 shots. Randy
Wakeman sells some extended ware vent liner, that he claims is 2x. I change mine every year and don't worry about it no matter how many shots I shoot (not over 100, but over 20). The Savage vent liner is well designed, and I know that size of the flash hole is important in ignition in Smokeless, so that is going to go over to BlackHorn, since it is so close to smokeless. So in my mind, any breech plug that will shoot Blackhorn consistently over hundreds of shots. Plain old BP or pyrodex, I don't think it matters, but with BH or Smokeless size of hole is big deal.

I like the flat breech plugs since the convave ones leave power in the hole and it sometimes is difficult to get out if your shoot a lot and you got soot in there.
Chap