This will be the third issue of reloading 101 and we’ll go through everything needed to set up dies for a straight wall cartridge. I have two cartridges I’ll refer to in this section but the techniques can transfer over to many other cartridges. There is a lot to discuss, so let’s get started.
Straight wall cartridges can be referred to by two different types depending on how they headspace. Cartridges that headspace on the rim and usually put into revolvers use a roll crimp, like the 45 Colt. Others that are typically used in pistols for self-defense, like the 45 ACP, use a taper crimp because it headspaces from the case mouth. Both types can have the same sizing technique but have a different crimp style that you may be able to see in the photo. These are dummy cartridges (no powder or primer) that I use to set up the seating dies and I’ll explain them later.
To start with, there are several different dies that you can choose from depending on your price range. Some are fragile and can crack if used improperly but others are tough enough they will last your entire life and not show any noticeable wear. At least one manufacturer has three different sizing dies for straight wall cases; a standard steel, a titanium carbide, and a dual ring carbide. The standard steel can be screwed down to touch the shell holder with no ill effects but I don’t go down that far with them. The titanium carbide is a lot harder metal and if enough pressure is applied to it from the ram, it will break so keep it up and off the shell holder. The same goes for the dual ring but let’s go through their differences. The standard as well as the carbide size down to only one diameter. By running it all the way down the length of the body, a small diameter is created in the middle after the bullet is installed. This gives the cartridge what looks like a waist if it is small enough so the dual ring was created. The top ring will size down enough to hold the bullet securely but the bottom ring is sized just enough to keep the body of the case looking normal and fit correctly. Personally, a lot of my dies at home are the single ring carbide because I just wanted to eliminate the need for lubrication. In my revolver cartridges, I only size the portion of the neck that holds the bullet anyway. This is only because I’m putting brass back into the original firearm it was shot from and keeping my pressures low enough not to stress anything. In a semi-auto, that luxury isn’t available because reliability makes me size the entire length of the case.
Now that the case is sized, the second die will expand the case neck back out to just under bullet diameter. In the photo, you can see the step of the expanding stem that flairs the case mouth open for easy bullet seating. This stem should be positioned to only flair the case mouth enough that a bullet will sit on it without wiggling. Any more than that and the case can be over worked and reduce its lifespan. All straight walled cartridges will need this same procedure.
The next step is to seat the bullet. Personally, I crimp the case after I’ve seated the bullet and that is the way I’ll be describing it here. If you don’t have a dummy cartridge already, you’re in for a treat so let’s make one. You’ll need to feel your way into the die by raising the ram all the way up with an empty case in the shell holder. It may touch the inside of the die before the crimp portion is reached so examine the case often. Once you begin to see a crimp being applied to the case, back the die body up and off by at least a half to a full turn. You can now install the seating stem and begin working a bullet down into another case. Once you get the bullet into position, you can now apply the proper crimp. If a dedicated crimp die isn’t available, the seating stem will need to be removed and the die body screwed down until the proper crimp is applied. From now on, the die set up will be a lot easier and this is also a good place to examine the different crimps. The roll crimp is simply that; where it rolls the case mouth into the bullet but it needs a cannelure (a relief area) to put it into. When I put a roll crimp on a cartridge, I’ll put it on as heavy as I can without bulging the case neck below it because I want the powder to burn as well as possible before the bullet has a chance to leave the case. A taper crimp on the other hand needs a lot lighter touch. It is critical that the case mouth catch the part of the chamber designed to hold the case back under spring pressure from the firing pin. I’ll measure what the diameter of the case is around the bullet and make my crimp around 0.002” or so smaller than that at the case mouth. This won’t hurt headspace but still give a little more hold to keep the bullet in place.
Now that a dummy round is made, we can change the die set up technique for future tasks. Before I even screw down the die body, I’ll put the cartridge in the shell holder and raise it all the way up. Then, I’ll screw the die body down with the seating stem removed until I feel it touch the case. The crimp portion of the die is now resting on the case mouth and because I don’t want to crimp just yet, I’ll back it off a half to a full turn and lock the ring down. Just remember to apply pressure to the die from the handle using a spacer of some kind when you do. Now, you can screw the seating stem in until it touches the bullet and that lock ring can be tightened when pressure is applied. All of the bullets can then be seated and after that, I can set up to crimp and the one thing I don’t want to do is move the bullet when I apply it. I’ll usually take the seating stem out of the die body if I’m using a single stage press and don’t have access to a dedicated crimp die. After it is out, I’ll screw the die body down until it is putting on the proper crimp and finish my ammo.
Now, we’re making ammo and hopefully having fun doing it. These are teachable techniques, so if you can, get the kids involved and have them pull the handle for a while. Someday, they may even thank you for it, especially when they are having fun shooting what they have made at the range.
Till next time, have fun and be safe.
Please note: These dummy rounds were made a long time ago when I first started loading for them. You will notice rings around the ogive and this is created by the seating stem having a bur where it touched the bullet. Since then, I have been able to smooth the inside of the stem as you can see in the photo. This will go a long way to making better looking ammunition.