Just in case anyone is interested: On the second one I did I started using a end mill with a 40degree angle on the end of the bit to finish the seat for the vent liner. 25/64 in diameter this gives a match to the base of the vent liner for a better seat. Lee

Don't know if this is relevant or not, but in the Accura breech plug, the flash hole seems to be just that. The flame channel is almost the full length of the breech plug. Whilst drilling out the flame channel, it seems one could easily drill right out the end of the breech plug by not noticing when one was at the end of the flame channel. The Omega breech plug has a flash hole that is considerably longer. This is one thing i considered, but then it seemed like the vent liner would be more better; perhaps not.

Oops, it isn't as extreme as i thought. The Omega breech plug has about 1/4' from the bottom of the flame channel to the face of the opening, while the Accura breech plug has about 1/8" from the bottom of the flame channel to the face of the opening.

Yes I did Mike, but now with your Professional experience my ACCURA BP will be on it's way to youand as Always Thank You!
Ron (BP)

Am i to understand that if i use my 25/64 drill that seems to have about a 30* angle on the end of it, i will have a situation where the vent liner won't marry up to the breech plug very cleanly. I don't know if i can grind that much of the end of the drill without ruining it. So, i should be looking for that specific end mill?

ronlaughlin

That 30 degree angle will work... it is a lot nicer to have the 40 degree - but the last one I did I did, was with the drill bit as you are thinking. When you install the vent liner - you will use BP grease on the threads and under the hood of the vent liner. Snug the liner up and compress the grease. I shot 30 rounds the other day with a Knight (T7), removed the breech plug and un-screwed the vent liner no problem.

Other alternative - take the bit to a machinist and have him change the angle for you.. he can do it in a hurry.

So if you and I get our Flash Channels drilled out
I guess we'd have to measure the exact length of the flash channel and go no further, simple as that right? Or measure the length from the top of the BP to the end of the fire channel.
(BP)

Breechplug

Exactly what you have both said... you will have to measure the current depth and set your drill press to go no further... Or dill all the way through and tap the bottom and install a vent liner...

Breechplug

Yes, that is what we could do, and it isn't as difficult as i had it in my mind it was. I think it is a worthwhile first step toward improving the bp.

What i wanted to do originally was make a deeper concavity in the bp, and drill out the flash channel, but then i realized there isn't enough material there to allow the deeper concavity. So i decided to try the vent liner and forgot that one could drill out the flash channel without making a deeper concavity in the end.

I guess i will give it a try on Saturday. Like sabotloader say, when the flash hole wears out, one can proceed to install a vent liner.

sabotloader

Well, i guess it is a good thing the 25/64 drill will work, because it doesn't appear that a 40* end mill is readily available. Seems to me that it would be best if the rim of the vent liner made first contact with the breech plug. Like you say, i can make that happen by grinding the drill to a steeper angle than 30*. Seems that if the angle were ground too steep, it would be better than if it were too shallow.

I guess i will start the modification before the vent liners arrive, by drilling out the fire channel with a 5/32 drill, then when i have the vent liner in hand i can drill again, and through with a #21 drill. Doesn't seem as though it will be much of a problem. Time will tell.

Your drill will work fine, The taper on the Savage style vent liner screws is listed as 82* . You can geta 82* countersink, this is what I finish my holes with now. The reason for the 25/64 drill is the average head diamater of the vents is 3/8" + 24/64. Some are smaller. I shot my rolling block over 400 times before I got the 82* countersink. You will be fine.

As a point of interest, the original ML10 that uses the modules also uses a vent liner, but this vent is made from a 10/32 set screw, these have no head as a screw does.

I make my own vents fro 10/32 x 3/8 Holo Krome screws, these are the same screws as the OEM savage and most of the aftermarket suppliers use. I drilled 28 last week, I got Cobalt drills for this. I start the holes using a .062 Cobalt drill This is to get threw the hard surface of the screw on both ends, this is what will break the .0315 cobalt bits. I use the .062 from both ends then finish the hole with a .0315 cobalt drill . I am still using the origonal .062 drill but have only been able to get 14 screws out of the .0315 bits. 14 is my best so far. I do use my lathe to bore these but there are many that use a drill press.

I have not tested the Leighi style vent screw yet . But my next purchase of a box of 100 screws will be with the doomed head.

There is no reason that the plugs can't be reworked with just a drill motor! Clamp you plug securely and drill as straight as you can. It has been proven on other boards/ groups that a crooked hole in the vent liner will not effect it's performance!!! Have you ever really looked at the flash hole in a lot of brass cases. Oem Vents from savage will not always be centered.

With that said have at it!

One of the things I live by is:

"God hates a coward, but is very tolerant of fools!"