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Old March 1, 2014, 07:02 PM   #17
B.L.E.
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Join Date: December 20, 2008
Location: Somewhere on the Southern shore of Lake Travis, TX
Posts: 2,603
Quote:
Long ago I was working on a Subsonic Jacketed load for my 45-70. I was shooting Hornady DGS 500 grain bullets set really deep to function from the marlin action. A developed a trail boss load that was hitting about 900 FPS from my BFR (10 inch 45-70 revolver) but only getting about 700 FPS from my marlin. That told be the bullet was slowing down. These bullets are jacketed and very long so they have a lot of drag. I feel I am lucky I did not stick on in the barrel.
That's 898.4 ft-lb of energy verses 543.5 ft-lb of kinetic energy. Almost 355 ft-lb of energy lost in the longer barrel, which means if that rifle barrel is one foot longer than the pistol barrel, it takes about 355 pounds of force on the base of the bullet just to maintain velocity. The friction is probably higher since there most likely was still some pressure in the barrel.

With lead bullets, once started in the rifling, you can easily push the bullet through the bore with a ramrod. Get a jacketed bullet stuck in the bore and you'll need a hammer to get it out.
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