Quite apart from werewolves and other such entities, I believe silver bullets would be found to be effective against ordinary mortal humans.
Why not a super-soaker, filled with Silver Nitrate?
Winchester Silver Tip Hollow Points…
Everywhere fine firearms are sold.
Go ahead, Broomhilda, make my day.
I’ve always liked the idea of shotgun shells filled with blessed rosary beads. Wooden ones for vampires and silver ones for were-creatures. It’s the cold iron projectiles that are a bitch, for the fey. ;>
Damn. Herb stole my contribution. I was going to say that you can easily buy Winchester Silvertrips, at least for a .38.
According to this, you can get it in pretty much any handgun caliber you want. Catalog | Winchester Ammunition
Hypothecially, if you were facing vampires, I don’t see why you couldn’t get regular lead bullets and use a knife or something to carve a cross into the point(one line, then another bisecting it. Good enough for government work).
Unfortunatly, Witches can only be killed by water or by dropping a house on their heads. 
I remember when I was in the service in the barracks watching Bugs Bunny, where Yosemite Sam has a dragon. A guy stood up and left during the cartoon, violently pissed because GREEN dragons do not breath fire… only RED dragons do that.
People who debate dragons and vampires and stuff are scary folk.
You are writing a short story, not a Clancy novel. Just make it clear that the guy made his own silver bullets, ala Estes in Darkest Hearts by Nancy Collins (Sonja Blue books, which to me by far are the only vampire books worth reading… Anne Rice is shit). The reader doesn’t need to know how, unless you are just killing time. Are you telling a short horror story or giving a class on internal ballistics?
In any event, bullet molds are available through any dealer and even mail order. Remove original bullet with pliers or a kinetic bullet puller. Put silver bullet into case with original powder, reseat with a Lee bullet press. Silver is not hard enough to be a problem for the gun barrel. After a few thousand rounds yes, but not for a guy who waxes a witch a week.
What have you been reading about 20 gauge shotguns? My mom has shot three 200+ lb. deer at 100 yards with a 20 gauge that dropped in their tracks. A 12 gauge is a lot more powerful, yes, but a 12 gauge, like a 20 gauge is a fowling piece. That’s what shotguns are. A 20 gauge slug has more energy than a .44 magnum.
Also, when you are reloading, you aren’t seating a bullet into crimped brass. You crimp the brass after you reload. Stock and/or fired brass is uncrimped. You can’t have crimped brass without a bullet.
Actually, I think he’s remembering Bordello of Blood with Dennis Miller, Angie Everhart and Chris Sarandon.
The two guys (of whom Dennis is one) get to the vampiric bordello below by way of the old coffin-through-the-false-crematory secret route routine (I mean, talk about movie cliches!;)) and start shooting away with their holy water-filled water guns. All to the inspired music choice of Sweet’s Ballroom Blitz.
That movie cracked my stuff up.