Chambering question

W

WallyDog

New member
This is a question about chambering a barrel. More especially the area next to the shoulder. I have always relieved the last few threads with a squared off tool for about .100. So there are no threads for that .100 and I generally cut to the minor diameter of what would be the threads. That being said I used to cut off the entire tang when rechambering but have thought more about freshing up my throat every so often to keep the throat area cleaner for longer. So now the concern is that If I rechamber say .050 that makes my relieved thread area .150 then .200. Anything wrong with that accuracy wise? I cant imagine the few missing threads for up to .200 back would change much?

Wally
 
I remember in the old days I had a great barrel. When the tenon was cut back about 3/4" the thread relief was now about .825. It shot great. What is your concern? It takes only a few threads for strength.
 
Thanks

Butch Lambert said:
I remember in the old days I had a great barrel. When the tenon was cut back about 3/4" the thread relief was now about .825. It shot great. What is your concern? It takes only a few threads for strength.
Click to expand...
.

Concern is just effect on accuracy. I didnt think it would matter too much but figured I better ask.

Wally
 
I would go .025" at a time. If it takes .050" to get a fresh throat then the finish has probably deteriorated to the point that the barrel is gone.
 
Amend or full story on the above post.

I pulled that barrel out of the grave. It was a Teddy and it was set back .500 and the original threads were used.
 
Setting back

When I’ve set back, I try first about 1/2 a thread. I’ll get my bore scope out and look at how square the lands look. If they are rounded or bullet shaped I’ll run the reamer in another 1/2 to see if Im in far enough that the lands are square. I’ve seen good shooting barrels set back so many times there’s only 5-6 threads left before, but that seems pretty extreme to me.
 
On my 6PPC barrels, I set them back about .030 after each 350 to 400 rounds. I will do this twice, then chop the entire straight of the chamber off and treat it like a new blank. The way I chamber barrels allows me to set a barrel Back up exactly the way It came out the first time.

That is the only reason I do not cut a thread relief. There is a counterbore in the action anyway, so all that area fits is air.

I am really anal about throats and seating depths. Probably a little too anal.
 
18TPI =.055 per revolution

jackie schmidt said:
On my 6PPC barrels, I set them back about .030 after each 350 to 400 rounds. I will do this twice, then chop the entire straight of the chamber off and treat it like a new blank. The way I chamber barrels allows me to set a barrel Back up exactly the way It came out the first time.

That is the only reason I do not cut a thread relief. There is a counterbore in the action anyway, so all that area fits is air.

I am really anal about throats and seating depths. Probably a little too anal.
Click to expand...

This is a Speedy built rifle and I figured he might have indexed the barrel. Since 18 tpi = .055 per rev I decided on that as a way to stay indexed? Also the engraving on side of the barrel still shows in same rotational location. I finished it up today and ended up at 2 revs or .110 setback. The throat is pristene again Jackie! Lol. Id forgot what a pain it is to make cases. Made 50 and it was half a day by time I fired, reamed, neck turned them all.
Wally
 
You must log in or register to reply here.
Back
Top