257-78-FN (Bob’s Boat Tail) (7)

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  • #504689
    stephendampier
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      add me to this list please

      I’ll need a bit more information for that to happen.

      5 cavity aluminum with Hollowpoint. I’d love more than one Hollowpoint cavity if possible.

      #504690
      adamsutherland
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        List updated.

        #504691
        daleriggert
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          ” I Want ” a 4 cavity brass please .

          #504692
          adamsutherland
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            List updated.

            #504693
            rsterne
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              NOTE:

              Recent results indicate that my Bob’s Boattails seem to stabilize in a slower twist rate than predicted…. We don’t have any firm data on this bullet (because it hasn’t been made yet)…. but I have a feeling it may be just fine in the standard 14″ twist TJ’s barrel in common use for .257’s….

              Bob

              #504694
              malcolmmunday
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                4 cavity Aluminum with Lyman HP pin, please….

                #504695
                adamsutherland
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                  List updated.

                  #504696
                  rsterne
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                    I have informed Al that I have a revised design for this BBT, with less taper on the boattail…. This change was made at the suggestion of UK Ballistician Miles Morris, to help insure that the flow reattaches behind the boattail rebate, which has also been made less abrupt….

                    https://hosting.photobucket.com/images/oo221/rsterne/New_257_cal_BBT_78_gr(1).jpg?width=1920&height=1080&fit=bounds[/img]

                    I have sent the new drawing to Al…. This change will also insure that it works in a 14″ twist…. Information in blue is for scaling the bullet to other calibers (twist rate proportional to caliber)…. I hope NOE can get around to this design soon, as I think it would be very popular….

                    Bob

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