Pre-64 Mod 70 bbl fit

B

bob3700

Member
Gents,

I am in the process of re-bbling my first Win M70 Pre-64. I took the bbl off the action so that I could measure everything up. Was most interested in how I was going to mark the bbl for the extractor cut.

Here is the problem. With all the dimensions taken, I thought I would screw the old bbl back on and check out the alignment of the extractor cut. It won't align? What the heck?

I did nothing to any of the components, just measured them. The extractor cut is off by 10-15 degrees high and I have put 85 ft lbs on the thing to reassemble. How can any of the dimensions change like that? I checked for the obvious, a bur on the action or bbl shoulder. Looks good.

I know that the recoil lug is high but the darn bbl was on there originally and everything lined up.

Any thoughts/experience out there would be appreciated.

Bob
 
Here is what I do. After final chambering and fitting, the next thing is locating the cut for the extractor. To do this, barrel is tightened to the action and, while still in the barrel vise, I take a tool I made from 1/2" x 10" drill rod. It is milled flat on three sides with the two opposite flats milled to fit the inside the receiver at the bolt lug raceway, and a concave cut made on one end. I then harden the end so what I have is esentially only a marking tool. Insert it into the raceway, on the correct side, (don't ask how I know) and tap the end to mark the barrel. Remove said barrel and move to milling machine for cut.

As for the other problem, I have no idea what is wrong. Try it again, it is April 2nd. Was wondering how you intend to mark the new barrel using the old one for reference anyway.
 
Dennis,

No it is not an April 1 joke. This has really happened to me and has be puzzled.



Jkob, I was going to prussian blue the back of the breech and then in a similar method, mark the extractor cuts based on the right lug recess.

The original bbl not lining up again has been the biggest issue. Has me baffled.

Bob
 
bob3700 said:
Dennis,

No it is not an April 1 joke. This has really happened to me and has be puzzled.



Jkob, I was going to prussian blue the back of the breech and then in a similar method, mark the extractor cuts based on the right lug recess.

The original bbl not lining up again has been the biggest issue. Has me baffled.

Bob
Click to expand...

That is very puzzling... all I can think to grease the shoulder/face of the receiver and whack the wrench a little harder... if you come up a degree or two short, remove two thou from the barrel shoulder and try it again...
 
If the cut for the extractor is high then you have over torqued the action on the barrel. There should have been a mark on the barrel and action for alignment. O.W.L.
 
owlshop said:
If the cut for the extractor is high then you have over torqued the action on the barrel. There should have been a mark on the barrel and action for alignment. O.W.L.
Click to expand...

That's a good catch... I just assumed he meant the action was high on the barrel cutout and he couldn't rotate it enough ...

Now we need a reply from the op confirming what's what.
 
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