Ha ha. Zombie Dart. Love it. I would use the Valiant as a weapon, but I haven't put in the ram bar yet. :P
And yes, many 9mm applications also accept .45 rounds. The same is true with .38 and .357 rounds. Both are handy because any gun shop will have plenty in stock, and most law enforcement carry either 9mm or .38 ammo. I stick with the 9 mill for larger brain destruction. Some prefer .22 because it can enter the eyes and rattle around in the skull destroying the brain completely, but IMO it's hard enough to hit a head in a stressful encounter, let alone the eyes!
You can tell I've researched this too much. I will slink away now.