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dcb
01-19-2008, 05:11 PM
what are the correct steps to chamber a barrel.
Do you cut the chamber then the tennon and threads?
or cut the tennon and threads then the chamber?
thanks Dave

Butch Lambert
01-19-2008, 06:12 PM
You can do it either way.
Butch

PEI Rob
01-20-2008, 12:14 PM
Being new to this I decided to chamber first using the drill then taper bore method, through the headstock. I like to chamber deep stopping with a good finish then face, do the mouth radius and polish up. If all is perfect with the finish then I'll thread and headspace. My reason is lack of chambering experience so I'm much more confident in cutting the shoulder and facing than stopping the reamer where I should with a good finish. Most guys here don't have that problem.

Cheers,
Rob

PPP MMM
01-20-2008, 01:45 PM
what are the correct steps to chamber a barrel.
Do you cut the chamber then the tennon and threads?
or cut the tennon and threads then the chamber?
thanks Dave,,,,,,,,,,,,,,,,,,,,,

The turning of the tennon and cutting the thread is far riskier to dislodge the barrel set up by hitting the shoulder accidently, than the drilling and cutting the chamber is. As accidents do happen it's better to get the risky(tennon/thread) part out of the way first and do the light work on the chamber last.

Shoot well
Peter

RoyB
01-20-2008, 03:03 PM
I would be concerned that if you chamber first, and then remove all that metal around the chamber, that the chamber will grow some.......

Also, I like to set headspace with the action and bolt threaded onto the barrel. Can't do this until the threads are cut.

Butch Lambert
01-20-2008, 03:07 PM
RoyB, You can't do that on a glue in.
Butch

RoyB
01-20-2008, 03:27 PM
Hi Butch,

I understand. But I didn't see him asking about a Glue In...........But even if you are headspacing from measurements, the issue of the chamber expanding still exists, correct?

Butch Lambert
01-20-2008, 03:40 PM
If and that is a big if!, I don't think that you could measure it. It is a nonissue.
Butch

jackie schmidt
01-20-2008, 04:11 PM
I believe that is a non issue as well. If removing around .140 inch diameter from a typical 1.200 Sporter Shank causes the bore to change any measurable amount, I would like to see how you are measuring it.
I rough the tenon out to within .005, then establish as good of a chamber as I can in the barrel. I then perform all of the other machining operations.
The reason I rough the tenon out is that is the only time that there is any appreciable tool pressure to possibly disturb the set-up.
Incidentally, after I establish the chamber, I check it and the throat area with the .0001 indicator to insure that it is as it should be..........jackie