Rifleing

Discussion in 'Gunsmithing' started by dumbear, Sep 1, 2011.

  1. dumbear

    dumbear Active Member

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    How is it possible for a rifle bore to be slightly tighter at one end. I have a TC .50 cal muzzleloader that is slighter tighter towards the breech end than at the muzzle.
     
  2. J E Custom

    J E Custom Well-Known Member

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    Normally they are not. But when they are (Within specs.) the barrel maker marks the tightest end for the muzzle.We are talking about 1/10,000 of an inch, the normal maximum allowable.

    This allows the bullet to stay in contact with the barrel all the way down.

    If it is smaller at the breach end this is not conducive to good accuracy.

    J E CUSTOM
     

  3. rscott5028

    rscott5028 Well-Known Member

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    The barrel could also be dirty or fouled.
     
  4. denphillips2

    denphillips2 Well-Known Member

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    How are you determining that it is tighter at the breech than the muzzle?

    If it is just getting tighter while seating a bullet, it could be dirty/fouled, rusty, rough, or tight.

    Tell us more and we will be able to help more.

    Denny
     
  5. dumbear

    dumbear Active Member

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    I never noticed it w/saboted bullets. I decided to try the Thore full bore dia. bullet which is made by Barnes for Thore. They send a sizing pac which has bullets of .500,501,502,503 etc. The 501 felt about right as I could push it w/two fingers on the ramrod to about 8 in. in front of the breech plug,then it pushed slightly harder but easily seatable. This all on a VERY clean bore. At the range that last 8 inches became a pounding match and I knew these .501's were not going to work. I know this was due to fowling at the range......but, even on the clean bore they were tighter in that last few inches.
     
  6. denphillips2

    denphillips2 Well-Known Member

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    Which TC is it? Is there anything on the outside at that point that could be affecting it? I have felt roll engraving on the inside of .22 barrels while slugging. That is the point that does get the most fouling. I would try scrubbing the crap out of it with JB, Flitz, Isso, or Rem Clean(40X). Then try it. You could always have it lapped also, but before I would stick any money into it, I would call TC. They are pretty good on warranty.
    Hope this helps!
    Denny