shortening the throat on a barrel

[41magsnub]

I have a Ruger M77, the old tang safety one from the 70's, in 7mm mauser. This rifle has the over length throat for the long nosed mil-surp rounds which makes it not even remotely accurate with the factory 140gr rounds I have tried. It does ok with the 175's.

I am taking up reloading so I can make a load that it likes later this summer that is not as anemic as the factory 175gr stuff (as well as for other calibers) when the funds get saved up.

This is all reasonable.

However, a buddy of mine said that is is possible to have a gunsmith shorten the throat so that it would work better with the 140gr factory loads. I'm not seeing how this is possible but I also don't know what I am talking about. How would a gunsmith go about shortening the throat??? Take a slice off the back of the barrel and then bore the chamber again?



Either way I don't really have any intention of screwing with it like this since it is a beat up old deer rifle missing much of the bluing, it is just a curiosity thing. I also like the reloading idea much better because my only costs are the caliber specific components, since I was going to get the press and standard peripherals anyway.

 

[rcmodel]

The only way to shorten the throat is as you surmised.

Cut off a barrel thread or two, set the barrel back one or two turns, and recut the chamber with a chamber reamer with a shorter throat section.

It may be possible, depending on magazine length, to long seat lighter bullets closer to the throat when you get into reloading for it.

On the otherhand, Ruger and others got out of throating, and into what we used to call free-boring in an effort to reduce pressure below industry standard.
It was a lawyer thing and accuracy be damned.

rc

 

[41magsnub]

Thanks RCModel. I have a load bookmarked that will be the first one I try which uses a 140gr seated way forward which other folks with the same rifle have used successfully.