If you mean how heavy is the bullet in a .40 caliber cartridge, the answer is, it ranges from about 150 grains to about 180 grains.
9mm diameter is .355 40 diamerter is .40
No
what does a40 cal. bullet look like
40 cal ACP (not CAP) is the same as 40 cal. S&W. ACP refers to 'automatice cartridge pistol' wheras S&W refers to Smith and Wesson, who also make the 40 cal. cartridge....
40$
All else being equal, the one that has more foot pounds of energy.
No, never attempt to fire ammunition in a weapon it was not designed for!.
40 cal
uuhhh... no, you cannot fire a 9mm parabellum through a .40 s&w.9mm converted to inches is .35 now you see that .40 is a little wider.
40 bullet penetration kills with full metal jackets (FMJ) selected.
100-400
The .40 cal has a larger bullet diameter, typically heavier projectiles, and, due to having a larger casing, produces more energy. 9mm variants of pistols can typically hold more rounds in the magazine than the same model of firearm can in .40, however.