momentum is the same thing as recoil, in the opposit direction. 50 grs at 4000 fps has the SAME recoil, same momentum as 200 grs at 1000 fps. But the heavy, slow load has 450 ft lbs of energy and the 50 grs at 4000 fps load has 1800 ft lbs. If you "think" that such a .45 ACP swc load hits like a 22-250 softpoint, you're an idiot. It does nothing of the kind. that 22 centerfire rifle softpoint will blow your guts out on the GROUND if it hits your abdomen. So people who CLAIM that energy makes no difference are quite provably fos. So then the issue becomes one of "how MUCH of an energy difference does it take to have a useful increase in performance?" that's a different kettle of fish.
now, you can have a 200 gr lrn at 650fps from a 2" .38 and it will barely pierce a windshield.(if it does so at ALL, which I doubt) Or you can have a solid aluminum 65 gr swc bullet at 2000 fps from a pocket 357 Sig. Same recoil/momentum, but I suggest that you not try to hide behind even THREE windshields between you and the pocket sig load.
Energy, in physics, is defined as "the ability to do WORK". When you are dealing with less energy, less work can be performed.
now, you can have a 200 gr lrn at 650fps from a 2" .38 and it will barely pierce a windshield.(if it does so at ALL, which I doubt) Or you can have a solid aluminum 65 gr swc bullet at 2000 fps from a pocket 357 Sig. Same recoil/momentum, but I suggest that you not try to hide behind even THREE windshields between you and the pocket sig load.
Energy, in physics, is defined as "the ability to do WORK". When you are dealing with less energy, less work can be performed.