open up M70 to 1 1/16" x 16 tpi ???

Discussion in 'Gunsmithing' started by rscott5028, Apr 11, 2011.

  1. rscott5028

    rscott5028 Well-Known Member

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    What are the pro's and con's of opening up a Winchester Model 70 reciever from 1" x 16 tpi to 1 1/16" x 16 tpi to match the Remington 700 threading?

    (it's a late model push feed)

    I have a wide variety of rifles and now that I have a lathe, I'm thinking it would be nice if every rifle had the same threads to give more options. Obviously, I can't do this with my Savage, Mauser, Steyer, Kleinguenther, etc.

    But, I see where some have done it with their M70.

    ... or is it just time to go with the herd and trade them out for 700's?

    I told my son the Steyer might have to go in order to pay for some of this and it was like he just lost his best friend. :-(

    Thanks!
    Richard
     
  2. J E Custom

    J E Custom Well-Known Member

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    There is nothing wrong with the 1" dia. just stay with the 1'' 16 tpi for the tennon .

    I dont recommend opening up an action unless it has bad threads and needs re cutting
    or truing.

    Ether way the strength is still there.

    If the threads need to be cleaned up do so and machine the tenon threads to fit (It
    still doesent have to be 1'' or 1 1/16'' just a good fit.

    There is nothing magic about the 1 1/16 TPI. Weatherby and Remington use it and
    Winchester and savage use 1'' tenons.

    J E CUSTOM
     

  3. rscott5028

    rscott5028 Well-Known Member

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    JE,

    Thanks for the good advice.

    I suppose there's no free lunch. Greg Tanner indicates he does this. But, I was thinking along the lines of being able to swap barrels between rifles.

    For example, I just got a 6mm barrel and 6BR reamer and was thinking I'd put that on the M70 long action now and later get a short action 700 to move it to. Obviously the headspace would need to be reset. But, matching the 700 threads now would make that more feasible.

    To your point, that may be overly optimistic if the subsequent 700 reciever threads have to be cleaned up and open up a little in which case, it won't be easy to get a good thread fit from the take off barrel anyway.

    ..plus the length of the threaded tenon doesn't match up either between Win and Rem.

    Whether we're talking about the barrel or reciever, once you take off metal, you can't put it back on.

    Thanks!
    Richard
     
  4. J E Custom

    J E Custom Well-Known Member

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    I am not a proponent of switching barrels even though people do it. They have to be head spaced
    with each barrel and as you take one off and screw the others on you lose your head space and
    thread fit eventually.

    And every time you take a rifle out of the bedding it deteriorates the fit and will loose accuracy.

    I like the 1 1/16 16 TPI and I see your point but as you said the tenons dont match anyway.

    What I was refering to was cleaning up the threads maybe .010 thousandths and fitting the threads
    of the new barrel to the receiver (The tenon threads would be 1.010).

    If you use takeoff barrels you will not get a good fit "EVER" because they are all different sizes
    due to the quality control at the factory and the acceptance tolerances.

    If you are looking for ultimate accuracy, It takes all of the elements in perfect conditions and
    the less you disturb them the better. (This is one of the reasons that benchresters glue the
    barreled action to the stock).

    The only system that I would use to switch barrels is the Savage with the barrel nut, And when
    I rebarrel a Savage I do away with the barrel nut because of thread fit and extra components
    that can lead to accuracy problems each time they are taken apart. (Two many variables).

    Sorry for the long winded explanation.

    Again this is just my opinion based on my experiences trying to ring out all of the accuracy
    possible.

    J E CUSTOM
     
  5. rscott5028

    rscott5028 Well-Known Member

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    I'm eager to slap something together. But, I have to keep reminding myself to hold out until I have everything I need to do it right. It'll cost less and the results will be better to just do it right the first time.

    Thanks!
    Richard