Originally Posted by
ronlaughlin
Screwbolts
Perhaps i should try doing the work on my Accura breech plug, before making a reply, but i can't stop my fingers. My concern with using a counter sink would be that it wouldn't allow a deep enough concavity in the muzzle end of the breech plug. After all, my main goal in reworking the bp was to make the face of the Accura breech plug look more like the face of the Omega breech plug. To me it seems the counter sink would make a concavity too close to the edge of the breech plug before it went deep enough to make this work worthwhile. Am i thinking clearly here?
You are thinking clearly, I forgot to say that my countersink is .375 diamater, (3/8 ) this is 1/64 smaller than your drill. I drill to nearly the desired depth, then us the counter sink to finish depth. The countersink I purchased for this is also Cobalt As long as I keep it cleaned and oiled it will out last me.
My breech plugs have an extended face that is .502 diameter this fits up the barrel slightly. about .187, the shoulder that seals is a step back. Now take .375 away from .502 that leaves Hum? oh Ya, .127 divide this by 2 for the wall thickness of the extended portion, .0635 or just slightly more than 1/16. But it has the same pressure on both sides In and out, (I did this because this is how savage/ Henry Ball does it)
This is the breech plug out of My Rolling Block, It started life as a Grade 8 Bolt 5/8 x 18 thread. Look at that primer seat extension, Holy Crap RonL that looks like a piece of Grade 8 3/8 fine thread bolt.
And that is the end of the Fish whacker I use to remove it, the 2 notches don't show in this photo. This BP has experienced over 800 primers, or should I say Hot burning sensations.
There is a primer in the BP when the photo was taken
I hope this clears it up.
Life was meant to be fun!!!!