Several companies are now making .45 ACP with small primers. These are so-called lead free rounds. If you pick up any brass at the range, sooner or later you'll find a couple of these while you're trying to re-prime the brass. I checked around the 'net and found all sorts of differing opinions, so I decided to write to Hodgdon and ask them about it. This is the response I got:
Toss the small primer pocket 45 ACP brass into the trash bin. They are for lead free primers, special powders and fully enclosed bullets. The flash holes are enlarged making these cases undesirable.
Mike Daly
Cutomer Service Manager
Hodgdon Family of Fine Propellants
Hodgdon Smokeless Powder
IMR Powder Company
Winchester Smokeless Propellants
GOEX Blackpowder
Toss the small primer pocket 45 ACP brass into the trash bin. They are for lead free primers, special powders and fully enclosed bullets. The flash holes are enlarged making these cases undesirable.
Mike Daly
Cutomer Service Manager
Hodgdon Family of Fine Propellants
Hodgdon Smokeless Powder
IMR Powder Company
Winchester Smokeless Propellants
GOEX Blackpowder