Upward pressure on barrel ?

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  • JOHN COOK
    Senior Member
    • Sep 2009
    • 711

    #1

    Upward pressure on barrel ?

    How do you check the upward pressure on the barrel ? ( upward fore end pressure on the barrel to within specified levels)

    john
    “Then said he unto them, But now, he that hath a purse, let him take it, and likewise his scrip: and he that hath no sword, let him sell his garment, and buy one.” (Luke 22:36)
  • Parashooter
    Senior Member
    • Aug 2009
    • 819

    #2
    Observe amount of force (pressure or tension) needed to move barrel away from wood at forestock tip. Viable* methods include -
    • Educated thumb pressing up on barrel while fingers press on top of upper band.
    • Educated fingers pulling up on barrel while thumb presses down on band.
    • Applying bottom of muzzle to bathroom-type scale and pushing down on handguard or upper band.
    • Hooking fishing-type scale near muzzle and pulling barrel away from forestock tip.
    • Securing rifle upside down and hanging incremental weights from barrel

    *None of these methods will work if the upper band fails to provide sufficient clearance for observable movement.
    Last edited by Parashooter; 07-04-2014, 08:33.

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    • Marine A5 Sniper Rifle
      Senior Member
      • Aug 2009
      • 7450

      #3
      I always found it funny that people will pay a premium for a "straight" barrel, then put it in a stock with 8 lbs of upward tip pressure, which bends the barrel.

      jt

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      • Phil McGrath
        Senior Member
        • Jul 2010
        • 213

        #4
        Originally posted by Marine A5 Sniper
        I always found it funny that people will pay a premium for a "straight" barrel, then put it in a stock with 8 lbs of upward tip pressure, which bends the barrel.

        jt

        Is it really a bend or more flexed? I bend will stay bent but flexed can spring back........

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        • Marine A5 Sniper Rifle
          Senior Member
          • Aug 2009
          • 7450

          #5
          Originally posted by Phil McGrath
          Is it really a bend or more flexed? I bend will stay bent but flexed can spring back........
          A bullet, going down a non-straight barrel, would not know the difference between bent and flexed.

          jt

          Comment

          • PhillipM
            Very Senior Member - OFC
            • Aug 2009
            • 5937

            #6
            Question. Does 8# force exceed the modulus of elasticity of the barrel? If so, the barrel is "bent" if not, it is still straight.
            Phillip McGregor (OFC)
            "I am neither a fire arms nor a ballistics expert, but I was a combat infantry officer in the Great War, and I absolutely know that the bullet from an infantry rifle has to be able to shoot through things." General Douglas MacArthur

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            • Marine A5 Sniper Rifle
              Senior Member
              • Aug 2009
              • 7450

              #7
              Originally posted by PhillipM
              Question. Does 8# force exceed the modulus of elasticity of the barrel? If so, the barrel is "bent" if not, it is still straight.
              It is not straight when in its stock. It may not be "bent", but straight it ain't! A long barrel can have quite a curve before exceeding it's MoE.

              jt

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              • wolley
                Senior Member
                • Aug 2009
                • 235

                #8
                The stock is deflected more than the barrel. And we all know these rifles generally shoot better with "some" pressure from the stock.
                There is no magic number. It just needs "enough" and there is not an accurate way to measure it besides a calibrated MK1 hand.

                Comment

                • Motorcop
                  Member
                  • Dec 2011
                  • 32

                  #9
                  In reality there are some 03's and 03A3's that shoot better with no barrel pressure, in reality almost free floating, than with any pressure at all. I know because I have two in my collection that are almost free floating and they shoot very well. I have others that require at least some pressure before they will perform. A smart 03/03A3 owner will do some testing and figure out what his rifle likes best. It's a little more work but well worth the effort.

                  Rick

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                  • JOHN COOK
                    Senior Member
                    • Sep 2009
                    • 711

                    #10
                    Thanks for all the responses. I finally found my copy Of " The Book of the Springfield " by E.C. Crossman. On page 291 he goes into quite a bit of detail cocerning the improper fit and bedding a Springfield. Good book in my opinion but you must accept it was copyrighted in 1932. Some things probably have been found to be incorrect by now or the information has stood the test of time. The book I have still has the liibrary card in the sleeve of the front cover. It was signed out on FEB. 7 by D. T. Farley. Its rubber stamped (Property of U.S. Army), (Camp White ) ? , ( and Jan. 9 1947 Library, Letterman General Hospital, Presidio of San Francisce, Calif. A lot of information in this book.

                    john
                    “Then said he unto them, But now, he that hath a purse, let him take it, and likewise his scrip: and he that hath no sword, let him sell his garment, and buy one.” (Luke 22:36)

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