We've had all the other "What caliber For..." threads here or at THR. It is time to, uh, plant our stake in the ground and face this vexing question: What caliber for vampires?
The first task is to determine just which vampires we're interested in. It seems that authors regard the traditional vampire lore as a buffet they can pick & choose from.
For instance, Anne Rice vampires (ARV) seem impervious to modern firearms and crucifixes. IIRC, any injury done with mundane, non-vampire-specific weapon is instantly healed. Steakley's Vampire$ (V$) also seem poor candidates for any sort of firearm, what with their lightning-quick reflexes, ability to run 80+mph, and propensity to soak up multiple .44mag rounds in the chest and keep up the 80mph pace.
A more promising candidate would be Joss Wheadon's Buffy the Vampire Slayer/Angel (BVS) bitey folk. They are vulnerable to the usual vampire-specific means of dispatch (wooden stake & beheading for instant kills, sunlight & holy water for cumulative damage) and can be damaged by mundane weaponry, though they are very tough critters. They don't go DRT even from catastrophic wounds and wounds that would incapacitate a human sometimes only stun them for a bit, give them pain, and reduce their effectiveness. They heal up rather quickly (days, weeks, months) from damage done by bludgeoning, cutting, and penetrating weapons.
Katherine Kurtz also wrote a couple vampire books with vampires that could be harmed with mundane weapons.
So, I think one of the conditions for a WCfV thread would be the vampires in question have to receive some sort of damage from mundane weaponry.
Going from large to small
Nukes
Nukes would do the trick. If they are reduced to atoms, that is more than equivalent to beheading and the various radiation would likely have some sunlight-like effect.
Explosives
Delivered in any manner. Whether it is a keg of black powder strapped to their buttocks & set off or a RPG going COM, I think blasting them to bits or chunks will satisfy the "beheading" requirement. Large cannons would have a similar effect.
Large-caliber weaponry
I am thinking .50BMG & on up into the medium cannon category (12.7BMG-40mm cannon). Something that has enough energy and creates enough hydrostatic shock to tear apart the vampire with a round or two would be good medicine.
Small Arms
Here, it gets more interesting. The 9x19mm and 5.56mm are the favored rounds zombie dispatch, but I think they are ill-suited to a lead-slinging vampire killer. IMO, the ability to do damage to COM and degrade a vampire's effectiveness puts the larger-caliber chamberings in play. Also, vampires usually are not found in the large numbers of your typical zombie-apocalypse scenario.
For a shoulder weapon, I think a Tromix Saiga-12 conversion to a shorty (12-14" bbl) with a full buttstock, bayonet mount, and interchangeable chokes would be the bee's knees. The ability to use 12ga slugs, relatively quick mag changes, and respectable melee effectiveness are all in its favor. ESPECIALLY the 12ga slugs.
A .30-06 might be preferred for head shots at long range, but for house-clearing and ranges under 100 yards the Saiga-12 would be preferred.
Non-concealed handguns would be dominated by the large-caliber revolvers, though the .454Casull & more powerful chamberings might be more penetrative than necessary. I think the reasonable top-end would be .480 Ruger or .50AE (in DE or revo format).
Concealable handguns would be dominated by the 1911, IMO. In .45ACP.45Super or maybe the .50GI, for kicks. Others like the Glock 21 or Sig P220 would be serviceable, but not as concealable as ol' slabsides.
