I am considering the purchase of a Winchester CRPF Mod 70 action. The seller states: "The receiver threads are recut to remington threads plus .010 in., so the threads are not slotted as they come from the factory."

I have asked him to exlain why, but wonder about his answer.

Can any of you guys explain why this may be a good idea or not. I just don't know why someone would do this.

KB

KB

The Rem tenon is nominally .050" larger diameter than the Winchester and has the same TPI so it is physically possible to enlarge the Win action to accomodate the larger tenon. I suppose he enlarged an additional .010" to make sure that everything cleaned up OK.

Why? Only the guy who did it would know. If I had to guess - probably because take-off Rem barrels are easier and cheaper to come by and they could be fitted and re chambered for the Win action??

Good idea? Not for me to say. I don't know how the action would be marked to identify the modification for the next guy and I would suspect that the value would have to lowered, a lot, so it would be up to the buyer/owner to decide.

Ray

Thanks Ray.

Now I know that he didn't mess up the action if he did a good job. I think it is a safe assumption that he is a skilled machinist, so it's probably accurate.

Personally, I can live with the modification, because I'll have a custom barrel installed, and it should be no problem for a smith to cut the threads appropriately on the barrel shank, to match the receiver.

You are right about the price, because the asking price is what drew my attention. Then I learned about the details.

If anyone else wants to add their two or three cents worth of info, go ahead.

Thanks,
KB

Kabluewy,

The size of the threads is due to the tool used to open the threads. From Brownells:

REMINGTON 700 RECEIVER TAP & ARBOR

Mfr: MANSON PRECISION

A Real Time & Work Saver When Blueprinting 700 Actions

Hand operated, titanium nitride coated tap re-cuts and squares receiver threads in just minutes with complete accuracy. Eliminates the risky and complicated task of re-cutting internal threads on a lathe. Two, tapered and hardened, bushings and an extra long pilot, guide and center the tap in the boltway to prevent mis-cutting threads and ruining an expensive receiver. Threads are re-cut precisely .010" oversize and concentric with centerline of boltway for maximum thread engagement. After re-cutting the threads the tap serves as a receiver facing mandrel to square the receiver face with bolt raceway.

SPECS: High speed steel. Tap - TiN coated, 1-1/16" thread pitch. 10½" (26.6cm) long. Bushings - .701"-.704" diameter.

Catalog page 107
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The bottom of the action needs to be engraved with the tenon size if you should choose to sell it later.

Good Luck!

That is normal procedure for me when rebarreling a M70. It is an absolute + & you do away with those damn interupted M70 factory threads.

David Miller does it as a matter of course on his $25,000 hunting Rifles. But he does it on annealed actions. What would trouble me in buying one already done is whether the person annealed the action to recut the threads, and then, how did he retreat the action?

Ditto Doug

quote:

Originally posted by 22WRF:
What would trouble me in buying one already done is whether the person annealed the action to recut the threads, and then, how did he retreat the action?

There is no reason to mess with heat treating/annealing when doing this to these actions.

I regularly cut them to the larger 1 1/16+.010. When I rebarrel them I use the Manson Precision set up to true the action.

OK guys, I have to ask the big Q.

Why?

I build my own BR rifles and if I use a factory action I enlarge the thread only enough to straighten everything.

And does it really make that much difference in a Big W action?

Ray