Any pistol-caliber weapon is marginally effective compared to a high velocity rifle round, even the 5.56x45mm, and no handgun round, even the .357 Magnum, is guaranteed to knock down an opponent with one shot. The 9mmP, particularly in the hardball configuration, is known to penetrate through-and-through, doing less damage than something like a .45 ACP that will tumble, or a 7.65x39mm rifle round that will do significant damage via hydrostatic shock. A pistol is basically better than a club, but not by all that much.
Stranger