Safety Question About Reaming A Requalified Barrel

[milsurpcollector]

I bought a surplus 7mm mauser barrel from GPC this is one of the unissued ones 19" long.

 

The barrel was over reamed so I face off some material in the lathe.

 

When I put it back on the receiver to check headspace I didnt get it screwed on all the way before I rechecked the headspace because I forgot to trim the secondary shoulder enough (rookie mistake)

 

Anyway I need to re-ream now and I am wondering if I have enough material left to ream the chamber.

 

I still have 5 threads left on the barrel shank but the chamber area is small on these barrel

[Doble Troble]

If I understand the problem correctly it sounds like you're having trouble cutting the barrel so that the distance between the shoulder and the breech face meet the receiver ring and the inner "C" ring at the same time.

 

It seems that most folks used to rebarreling commercial rifles (non-Mauser without the inner ring) have difficulty with this too, and there are many opinions about what you should try to do.

 

I don't have an opinion, I only know how I go about doing it. I put the stripped bolt in the receiver and measure (with a depth guage) two things: 1) the distance from the receiver ring to the inner "C" ring and; (2) the distance from the reciever ring to the bolt face with the bolt closed.

 

I then machine the barrel so that the distance between the shoulder and the breech face is the same as measurement (1) above. Then I ream the chamber until the distance between the shoulder and the base of a Go guage is about 0.002" LESS than measurement (2) above.

 

This was confusing to me at first, I hope it won't be so bad for you. This approach has worked well for me for many rifles now, I hope its helpful to you.

 

Of course whatever you do, make sure to carefully confirm proper headspace before you start blazing away with hot handloads.

 

Have a plan, take your time, and you'll get that barrel on right.

 

As long as you haven't taken the breech back so far that you can't cut a shoulder for the receiver ring, you shouldn't be anywhere close to strength issues. But its your barrel and you're the one responsible for making sure that its safe. If you're still uncertain, posting a picture might help knowledgable folks give you better advice.

[milsurpcollector]

Thanks for the reply,

 

I know what i did wrong and how to fix it, I am not sure if there is enough metal in the chamber area to ream it again. I will post a pic later to show what I mean.

 

 

 

[BobVZ]

Colombian 7x57 barrels were re-bored and chambered to .30-06 back in the fifties. This cartridge is substantially longer than the 7x57. So unless you shaved off more than 6 mm of the breech end you should be ok. My guess is we are only talking about a ten thou or so.