Smith & Wesson Forum - View Single Post - Basic Ammo Question: The higher the grains, the more powerful the round?

murphydog · 11-30-2012, 11:41 PM

It's a complex question (the first one). Everything else being equal, a heavier bullet will generate more energy on target, but larger bullets mean less space for powder so heavier bullets are usually driven more slowly. Bullet construction also plays a factor, in that rounds that don't stay in the target don't transmit their energy fully. Plus, heavier loads equal more recoil and may be less controllable.

So, for example, the 125 gr JHP full .357 load has the best statistical effect of all loads, due to a combination of adequate weight, good expansion and driven at relatively high velocity. The 158 gr loads are no slouch either, so no one should feel undergunned with an expanding round in this weight.

There is no one "best" load for your 642, but many recommend the Speer Gold Dot Short Barrel 135 gr +P for defense purposes. You can practice with lighter loads, like 148 gr lead wadcutters or 158 gr lead, but you should be proficient with the self-defense load.