Remington barrel tenon setup

L

Lucky Shooter

Guest
I'm getting ready to do my first barrel job and hope to fit an old barrel to a 40X action.

This gun has a replacement barrel, the action has been trued and a 1/4" ground recoil lug has been added. The gun is presently a 6BR and shoots very well. The bolt has a Sako extractor and I plan to chamber the old .224 barrel in 220 Beggs.

I've pulled the barrel and made the measurements. If I duplicate the tenon measurements, I'll get the following clearances:

Bolt face to barrel face .030"

Bolt nose to end of counterbore .017"

Are these reasonable clearances for the Rem action ?

Will appreciate any info on the tenon dimensions.

A. Weldy
 
Thanks Butch

Can you recommend some better numbers ? Might as well do it right the first time.

A. Weldy
 
I use a maximum of 10 thou end clearance and 5 thou diameter clearance...
 
Be Very Careful!!!

When chambering a Remington 700 style bolt for a chambering based on the 220 Russian, (or 6mmBR), keep that counterbore depth at a dead minimum. no more than .005.
Why??. Because the web of those two cases is not very thick at all when measured from the face of the case to where the solid portion ends inside that case. If you counterbore too deep, you will uncover the solid part of the case, and the results could be, well, not pretty.
I would consider .005 just right.......jackie
 
I bore the bolt nose counterbore to a depth of .155 and open it up to around .695 for the standard Remington bolt. I agree with Butch. The barrel you have is set up pretty loose.

When I was getting started in gunsmithing Allan Hall told me that it was never a good idea to take the measurements off an old barrel if there was any way around it. You just don't know what the previous gunsmith was drinking that day.

I fitted a barrel to a bag gun that was a sleeved Remington that was glued in. I did use the measurements off the old barrel since the gunsmith that fitted it was supposed to really be a good smith. When I put it in the receiver the stripped bolt fell closed on a 'no-go' with just the weight of the bolt handle. I took the barrel out of the gun and re-indicated it in five times before I got it right. As near as I can figure there was about .030 excess headspace on the 6PPC. That's not a problem if you know it and fireform cases and never set the shoulder back but you can't count on subsequent owners knowing all that.
 
Jackie

It's not nearly as bad now as it was 30 years ago with the ballon head cases. I can probaly still find some cases that have belts on them from the chambers being chamfered on the front edge. They were tough to drive into a neck sizing die.

Here's the way I do all Remington's.


Tenon length is headspace -.010"

measure the depth of the counterbore on the bolt, touch the barrel tenon with a boring bar and bore to the measured counter bore depth. Automaticaly gives you .010" clearence. I go .001" short until the last pass then face off the bottom of the counterbore. Chamfer counterbore.

+.010" over bolt nose diameter for counterbore diameter. I've seen some wild shooting rifles when the bolt nose touched somewhere.

Just picked up that you have a Sako extractor. The counterbore should be set at .140" That will let you get more of the case supported in the chamber. .140" works for all cases with .010" clearence on the rim diameter. I don't like any less depth because when you chamfer the inside slightly you run the risk of the case kicking out from under the extractor when it clears the chamber and hits the side of the action. That would violate rule#1
Don't do anything to make the phone ring.

Dave
 
0.005" on both counts

When it will cause me any grief, I'll think otherwise.

Shoot well
Peter
 
There can be two correct answers here depending on the intended use of the gun.

I own a Rem 40X that was smithed several years ago by a very well known and respected gunsmith. This gun has had the bolt body sleeved in two places to reduct bolt wobble. At the bolt head there is 0.002" diameter clearance on the bolt head/barrel counterbore fit. There is 0.005" clearance between the bolt end and the bottom of the barrel counterbore. It doesn't take but one piece of powder residue to jam lockup.

On the other consideration, say you have your 35 Whelen and are in Alaska and Ole Brown suddenly appears. I think in that situation I would want about 0.012" bolt-end clearance and at least 0.005" clearance on the diameter.

Would there be a measurable accuracy difference in the above situations if the 40X chambered in 6PPC and a loose bolt fitted and a tight bolt fitted? I wouldn't bet on it. At least there hasn't been on my 40X.
 
Thanks for all the replies

I've made up two sets of dimensions based on .005" and .010" clearances at the bolt nose and at the breech face.

Time to get started.

A. Weldy
 
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