Start small and work your way up in size as you remove crud by rotating the bit. When you can no longer insert a bit, then you know to stop. I think my Omega will fit a 1/8" bit, but not at first 'cause of the crud factor. After that, I just soak it in solvent while I clean the rest of the gun, then come back to it.
You know, it's funny. The standard way to clean the M14's gas piston and plug has always been with large drill bits (#15, letter P, letter O). I would like some smaller drill bits with handles for my Omega, like these:
__________________
"Well if it ain't loaded and c0cked, it don't shoot." -Rooster Cogburn
Well dang man, that's simple enough to make using something like a 1/2" dowel for the handle and a little epoxy to secure the bit.
__________________
My wife says I'm totally nuts, but I think I'm Semisane.
Things I've Learned: (1) It's not possible to please everyone, but quite easy to piss everyone off. (2) If you love animals as I do, then you're not a vegetarian. (3) There's no need to act stupid, even if you're very good at it. (4) If you eat right and exercise, don't smoke or drink, you're going to die anyway.
Well depending on what powder you use, you might not have to drill out the flash hole. For instance, with Goex, Pyrodex, APP, JSG, and Triple Seven you can flush the flash hole out. BlackHorn 209 you might have to drill out the center.
I take the breech plug and remove all trace of teflon tape off it. The I saturate a patch with cleaner... usually Rusty Duck Black Off. I grip the plug with my thumb and pointing finger and then out the tool back on it and begin to turn it around and around. This scrubs all the fouling and gunk off the outside. Then I pug the 209 primer end and fill the inside of the plug with more cleaner. If its one of them open plugs, I use Q-tips and scrub the inside of it clean. Turn it over and do the 209 pocket end the same way. Then with a dry patch I wipe it all nice and clean.
If possible I run a fuzzy pipe cleaner through the breech plug. Or with it soaked in the flash hole, I hit it with an air compressor.
__________________
"Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body, but rather to skid in sideways, a total wreck, screaming Yahoo, with a big smile on your face."
I use a brush and some Hoppes on the outside and a 1/8 drill bit for the primer hole. I shoot a TC Pro Hunter. I use a breech plug thread brush dipped in Hoppes for the threads in side
I have never had to use a Drill Bit to clean the Flash Hole on any of My BP's. But I dont over shoot them at the range either. I carry a spare and after say 15 shots I replace it with a new one. And inbetween say every 5 shots I use a (Nipple Pic) it's a perfect fit for the flash hole, I just push it through a few times and Im good.
Now when I get home and clean the BP I soak it in some Foaming CVA Bore Buster for awhile, then toothbrush the threads clean. I then take a small brush from My Bore Brush set and clean the Flash Channel of the BP, then use the nipple pic for the fire hole. Then I take a Pipe Cleaner and insert it in the Flash Channel to dry it out and see if there's anything on it to be sure it's clean, blow through it, look through it at a light to make sure it's open and clean and Im done, it looks brand new.
(BP)
__________________
Those who hammer their Guns into plows will plow for those who do not. Thomas Jefferson