Off center primer strikes

Discussion in 'Gunsmithing' started by SOUTHPAWSHOOTER10, Jul 22, 2011.

  1. SOUTHPAWSHOOTER10

    SOUTHPAWSHOOTER10 Well-Known Member

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    I have a winchester model 70 that i purchased new about 10 years ago that has always struck the primers off center. My question is can this be corrected, and should i even bother with trying to fix it, as i have never had a misfire with it. Mainly it just bothers me that this rifle that i will never part with has this "flaw". What are some suggestions, and could someone point me in the direction of a good gunsmith that could take care of it .
     
  2. J E Custom

    J E Custom Well-Known Member

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    Most of the time the reason for this problem is a bolt face that is too large allowing the case to set
    of center. The bolt is machined and the firing pin hole is/should be, centered as well.

    The other thing it could be is the extractor not holding it correctly unless the firing pin hole is
    much larger than the firing pin.

    Ether way it is hard to fix without a new bolt and/or a new extractor.

    Try a fired case without resizing it with a primer only and see if it still hit it off center.if the
    chamber is large it will allow the round to set off center if they have been full length sized
    so the fire formed case should do better.

    Just a few possibilities

    J E CUSTOM
     

  3. SOUTHPAWSHOOTER10

    SOUTHPAWSHOOTER10 Well-Known Member

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    Thanks je custom,

    the firing pin hole is visibly off center as was the scope mount holes on the receiver, i had sent this rifle back to winchester to correct these problems. They did correct the scope mount holes with what i believe was a new receiver but they did not address the bolt issue whatsoever. I have neck sized only on some of the cases just to see if there was any real accuracy benefit, and there was some but the primer strikes are still off center. I probably am just being nitpicky about this and just wanted to see what other people had to say on the subject.
     
  4. westcliffe01

    westcliffe01 Well-Known Member

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    If you were to see the primer strikes on my savage 24 combination rifle, you would probably snort your coffee / adult beverage.... The strikes are light and about 1/3 the way across the diameter... But it is pretty reliable. I had lots of misfires until I replaced the firing pin with a new one, not a single misfire since, but certainly not the best design.

    Now wait until I tell you about the breech locking mechanism on that gun... About the 3rd or 4th trip out to the range with the gun I found that the breech would unlock from the recoil of firing. It scared the crap out of me. So I stopped shooting it until I figured out what was wrong with the thing. Well, finally after a complete disassembly, I discover that the breech locking pin (which has a triangular/wedge shaped point) was just barely engaging the notch on the receiver (hardly more than 0.030"). So I filed and filed and filed (it was pretty tough, definitely heat treated, but only about 30-35Rc). After getting no-where, I had to be more drastic and went to the belt sander. it took several rounds on the belt sander to increase engagement until finally it was back to filing and then stoning.

    In the end I got it to work nice, but have to wonder if I would have killed myself if I had loaded a 20ga magnum shell in the lower barrel. For a discontinued gun, it appeared not to have been fired much and wonder if the first owner had a similar experience after which it became a safe queen ????
     
  5. SOUTHPAWSHOOTER10

    SOUTHPAWSHOOTER10 Well-Known Member

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    Lucky that you knew something was amiss with that combo gun, i had a browning gti try to do that to me but i honestly can't tell you how many thousand rounds had been fired through it. A trip to the gunsmith fixed her right up and now she's ready for another hundred thousand rounds.
     
  6. 458win

    458win Well-Known Member

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    Gre Tan rifles in Rifle, Colorado can probably fix it for you. I had him do a few of my Remington with his bushing modification to the bolt face and firing pen. My reason was they were cratering primers from the firing pin hole being oversized. Pretty sure he can fix your off center strikes.
     
  7. SOUTHPAWSHOOTER10

    SOUTHPAWSHOOTER10 Well-Known Member

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    Thanks for the info, i'll contact them to see what they say.
     
  8. rscott5028

    rscott5028 Well-Known Member

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    There's an AGI DVD on refurbishing old millitary Mausers.

    One of the procedures they perform is welding the firing pin hole shut and then re-drilling it on center and with proper clearance. It's a pretty low-tech operation.

    I suppose you could purchase a replacement bolt and/or aftermarket one if they're made for anything other than Rem 700's. Either way, you still need a smith to check your clearances, headspace, etc.

    Gretan can probably do it for aesthetics. But, if you are chasing accuracy, then he may recommend truing the action and/or rebarrelling at the same time.

    -- richard
     
  9. SOUTHPAWSHOOTER10

    SOUTHPAWSHOOTER10 Well-Known Member

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    Thanks for the response, i will be contacting gre-tan in the future to see what they have to say about working on the rifle but currently funds are lacking and i don't want to bother them until i can actually get the work done as i am sure they are busy. As far as accuracy goes this rifle will easily shoot under moa since i floated the barrel and give it the loads that it likes. However, rebarreling and chambering in a 280 ackley improved sure seems like fun.