How deep can I go to rechamber?

K

kweisz367

Registered
Registered
Joined
Nov 20, 2018
Messages
4
Hello all, I am attempting to re chamber a post '64 Winchester model 70. I have a take off barrel to replace the rusted out old one. My question is in order to align the sight screw holes in the new barrel I need to cut the barrel shoulder back approximately .055-.060. This also means I have to cut the tenon back and push the chamber approximately that much further into the barrel. Is it safe to do that or am I getting to far into the tapered portion of the barrel? Will the chamber walls end up to thin? I hope this makes sense. I know I could just plug the holes and use optics but would rather not if possible. Thanks in advance for the replies.

Kevin
 
What caliber and what kind of chamber pressure are you contemplating? .055" probably not a problem. Another thing what kind of barrel, cold hammer forged probably not a problem.
 
Cartridge is 7mm Remington magnum. The type of barrel? I don't know that. It's a factory Winchester take off of the same caliber. Off the shelf ammo will be used. What ever the gun decides it likes. It will just be a hunting rifle.
 
I think the mag develops a fair amount of pressure but that should be a cold hammer forged barrel. If shortening .055" causes the barrel to be compromised you are too close to the danger zone anyway.
 
What if you measure the outside barrel taper in the area you are concerned about and see how much the barrel wall would be reduced? Then decide if you want to go ahead.
Setting old barrels back is nothing new but I certainly would not take just anyone's free advice on whether it is safe.
 
Tozguy said:
What if you measure the outside barrel taper in the area you are concerned about and see how much the barrel wall would be reduced? Then decide if you want to go ahead.

Totally agree, you are still guessing but the dia difference is a smaller number. Or you could run the strength calculations and you will still run up against the factor of safety, another guess.
Click to expand...
 
It would be so much easier to set the barrel back and headspace the chamber if you weren't trying to preserve the front sight clocking. Of course, being a Winnie, you'll need to re-do the extractor cut anyway. Go slow with your reamer and check headspace often.
 
Thanks for all the advice so far. Appreciate it. I will measure the barrel OD diameter tomorrow and post my findings for wall thickness. Good advice.
 
What you are looking at is the hoop strength of the barrel. There are formulas for this. Search online for "hoop strength rifle barrels"
 
It is all about the headspace......remember one thing plays against the other, lots of changes to do here one thing changes so many others
 
You must log in or register to reply here.
Back
Top