Do the 45 Schofield cases and the Cowboy Special cases need different dies to work??
Well, yes and no.
First off, let's start with a photo. Left to right below the cartridges are 45 Colt, 45 Schofield, 45 Cowboy Special, 45 Auto Rim and 45 ACP. This gives you an idea of the relative sizes and powder capacity of these cartridges.
Let's talk about the 45 Schofield first. Off the top of my head I think I usually load the Schofield with 1.9CC of FFg, as opposed to 2.2CC for the 45 Colt. That translates to about 28 grains of FFg Schuetzen for the Schofield round vs about 33 grains of FFg Schuetzen for 45 Colt. You may notice the Schofield bullet is very stubby. It is a 200 grain Big Lube bullet that I designed. The production molds changed the design a bit and the bullets are not quite so stubby. Anyway, the 200 grain bullet saves a little bit of lead and recoils a bit less in a revolver than the 250 grain bullet in the 45 Colt round. If you look closely, you will see that the Schofield round has a larger diameter rim than the 45 Colt rim. .520 in diameter if I recall correctly, vs .512 for 45 Colt. That is because when the cartridge was originally designed for the S&W Schofield revolver a wider rim was needed to engage the S&W extractor mechanism. The upshot is you need a different shell holder or shell plate for the Schofield round, it will not fit in the 45 Colt shell holder the way most companies make them.
Because the round is shorter, the seating/crimp die has to be screwed further into the press in order to allow the shell to ride up far enough inside to seat and crimp properly. Some brands of dies will allow you to do this, however depending on the specifics of the die, the shell plate may bump into the bottom of the die before the shell is all the way in the die. The good news is I use a standard Hornady 45 Colt die set to load 45 Schofield. This set does allow me to screw the dies in as far as needed.
So different shell holder needed, but a standard 45 Colt die set may work. Or it may not, depending on the brand.
I buy 45 Schofield brass from Starline, I'm pretty sure they are the only source of it.
The 45 Cowboy Special is a very new design. It was designed by a Cowboy shooter a few years ago who wanted to put very light loads of Smokeless into a 45 case without having the usual problems associated with light loads in the huge 45 Colt case. The 45CS mimics the 45 ACP in most aspects. It can be loaded with a standard 45 ACP die set, and the same Smokeless data for 45 ACP can be used for 45CS. However, the rim is the same dimensions as a 45 Colt, so the round will chamber in any 45 Colt revolver. This means that a standard 45 Colt shell holder or shell plate is used when loading 45CS.
Here is everything you ever wanted to know about the 45 Cowboy Special:
http://www.cowboy45special.com/