Home Forums Hunting & Shooting Gunsmithing Extractor Cuts

There are many ways to obtain the same result.. After I get the threads done and barrel hand-tight on the receiver, I make a witness mark at recoil lug center.. Then put the barrel in the vise and tighten/loosen 2-3 times, then make one more witness mark after tightening.. That one will be the operative mark.

Remove barrel, set up in mill with the 'tight' witness mark on top.. Center the mark with a TDC locater, then install the cutter.. Touch the threads, move it off, and drop down .5" plus 1/2 cutter diam. (.215).

Piece of cake..

I take it that with a .215 dia cutter that the resulting extractor cut has a slight radius on each side - correct, and if so, does this require a minutely deeper cut?

The cutter is .430 in width, not .215.. Therefore, when you 'touch' the threads, you dial the quill down .5 + .215 and you're centered for the cut.. It actually has a little tighter radius than it should (IMHO, and this is a PTG cutter specifically for the M70 cuts..) The depth of the cut is specific to the extractor nose extension.. All that's needed is to exceed that by a few thou to ensure no contact, dress the edges, then relieve and polish the cut surface at the chamber mouth and you're good to go.. Ensure that last part is done - always.. Or else the owner can get some real scratches on cases and you'll end up having to remove the barrel again and do it then..

I am old and I forge5 easily. I look and the print, center up the barrel and move to the correct "print dimension" and make the cut. Never had one fail to no be correct yet.

WiFowler
Another option I didnt see mentioned....just dont make an extractor cut. I've been flat breaching them like a Mauser for years and haven't had any problems. An old smith/friend of mine turned me on to that. He ask me one day why it must have the cone....I still havent found a good reason.
Charlie

And there you have it, folks; a man with balls enough to admit to doing something contrary to convention. The only real reason for doing the cone and the extractor cut is because that's the way the factory did it and most figure you have to have it that way. I've not seen where the cone helps feeding and I have seen where the extractor cut hinders feeding. One of my own model 70's has the barrel fitted with a flat breech and it works fine; better than fine, in fact. I still prefer to fit the barrel as the factory did but I don't look down my nose at those which are installed flat. Rugers are flat and they seem OK. GD

He's not alone. (and I know Charlie knows what he's doing, obviously) Other smiths have ignored the cone and just breeched it like the Mausers. IMVHO, that cone is what makes the M70 feed very, very well when compared to some others.. If the installer does not fully relieve the edges of an extractor cut including the edge next to the chamber, the resulting sharp edges can hinder chambering and/or cause case scratching. With all edges dressed and relieved, (and coupled with a properly tensioned and fitted extractor) this won't happen. Done properly and finished well, the cone will allow feeding of any style bullet - whereas, I've had some flat breeched models have certain bullets jam against the breech.. If everything's perfect, the cone won't matter as much.. But seldom is everything (feed rails, magazine, bullet style) perfect. Look at the cone as 'insurance'.. Why, if the flat breech is ok? (not a flame, Phil, honest) So are Mausers etc... And like you said - they seem ok.. But I've had a few Rugers in that cam jam a bullet nose.. Also those CZs - last one was in .458 Lott and it jammed the bullet nose against the breech about 40% of the time.. Really great problem in a DG rifle..

Knee mill, barrel secured through my index, with a woodruff cutter

The method I'll probably end up using. Thanks all for the input.

Did anyone notice how clean Malm's lathe was? Wow! Tell me you cleaned before pics. DH

I did notice that!

My grandfather kept his lathe that clean too when he was still using it.

I'm always suspicious of anyone who has their lathes and/or mills spotless...

Anyone care to post a pic of their mill (vertical) setup for extractor cut? I'm a "visual learner" . . . . besides which I toyed with a setup this weekend and am either being anal, over-thinking the process, or missing something simple. Not knowing the OD of the PTG cutter Redneck references, but using his setup method with a 1" OD woodruff cutter, it sure seems like there is a potential for the cutter to cut on both sides of the chamber.

Only if you go way too deep.......

If you flat breech a M70 or 03 Springfield, would that not make for a stronger action?

From what I have read, the cone does not support the case head as well as a flat breech.

This is a rough sketch of how I envision the setup in a vertical mill.

Maybe this will help:



This is a closeup of the cutter at work. I have to make two passes with this cutter to get the width that I need.


Good luck!

Clemson

There's no perceivable strength gain by flat-breeching an 03 or a model 70.
The Mauser has more meat to begin with, which makes it stronger, but in actuality, it's kind of a mute point. Winchesters and Springfields have proven their strength and worthiness for a number of years.

When you flat breech, you're going to have to remove a pretty fair share of material off the nose of the extractor to accommodate.

For an operation that is as easy to do as the extractor cut, as well as the better feeding properties that are normally obtained with the cone breech, I think I'd stick with it.

Bottom line is, a guy that knows what he's doing can make either one work like a charm. A guy that doesn't, will tell you why you can't.

Perfect !!!

Thanks, Triggerguard.

Many years ago, when I re-barreled some actions, it occured to me that you could make an 03 flat breeched.

I never tried it, because I had never read of it ever being done. I'm not going to do it now. I just wondered if it was possible.