installing a barrel

[Joe Portale]

Hello folks,

I am current building a rifle using a old military BRNO VZ Mauser 98. I have never barreled an action before so I am naturally a bit aprehensive. I will be using a headspace gauge when hanging the barrel to the action, but are there any tips or warnings that I should be aware of?

thanks.

Oh, if anyone is curious it is a 8mm rifle that I'm converting to a .243 Win for varmit and steel target.


------------------
Joe Portale
Tucson, Arizona territory

"The unarmed man is a subject, the armed man is a citizen."

[George Stringer]

Joe, the best tip I can give you is to buy a copy of Kuhnhausen's book, "The Mauser Bolt Actions; A Shop Manual" and follow his procedures step by step. You will probably need access to a lathe and a depth micrometer (preferred) or accurate dial caliper is a must. As a rule I don't install prechambered, prethreaded bbls but I can't remember the last one I installed that actually fit. Find out if the barrel is threaded with 60deg or 55deg threads. If it's 60 you will want to chase the receiver threads with a tap. Makes final fitting much easier. Good luck with it and if you run into any problems don't hesitate to post here or give me a shout via e-mail. George

[Joe Portale]

Thanks George,

It seems I broke your suggestions already. I ordered the Mauser Spoter kit from Midway. It does come with a pre-threaded barrel. And I ordered the Mauser book at the same time. Yes, I can get impatient.

I have access to a fully equiped machine shop and can use just about everything in there. When I go to actually set the barrel, and if the headspace off,(which it will probably be)is the adjustment a matter of removing some metal at the face of the threads or reciever as needed?

Also, do you torque the barrel into the reciever?
Thanks

------------------
Joe Portale
Tucson, Arizona territory

"The unarmed man is a subject, the armed man is a citizen."

[George Stringer]

Joe, with the 98 as you'll see in the book, the final shank length is the distance from the reciever face (secondary torque shoulder) to the face of the inner ring (primary torque shouder) plus .005". Once you get the receiver trued you should take 2 measurements. The one I just described and measure from the face of the receiver to the face of the closed bolt. The difference between the two measurements plus .001" is the amount you want a go gage to protrude from the chamber for correct headspace when the barrel is installed. Once you get the shank length faced to the correct length then insert your go gage and measure from the rear of the gage to the face of the breech. If it's more than what you want the chamber has to be deepened. If it less, then the chamber has to be faced back and the barrel shoulder moved back the same amount. When all this measures correctly, you are ready to put it in the receiver. There are two methods used for final installation. You can torque the barrel to 65-75ftlbs but the most commonly used method is by index marks. To do this just install the barrel as tightly as you can by hand. If you've chased the threads it should screw in easily. At 6 o'clock on the receiver make an index mark. Then come back counter clockwise on the barrel about 1/8" and index mark it. Then tighten with your action wrench until the two marks align. The 1/8" is just an average. I've seen a bunch that wouldn't tighten that far. If that turns out to be the case then tighten as far as you can and then make a mark on the barrel that lines up with the one on the receiver. That way if you need to take the barrel back off for any reason you can always take it back to the same spot. After the barrel is installed, check headspace with you gages. The bolt should close with a very, very slight feel on the go gage. And it should lack about 1/4" from closing on a no-go. George

[Joe Portale]

George,

Thank you very much!!!

Joe