Brass Gymnastics
There are a few different ways one can make a handgun-sized shotshell. For .45 caliber, one can use trimmed .410 wads inside a case. This works well for .45 LC shells but doesn’t give enough room for .45 ACP. One can use shotshell capsules (plastic capsules that hold shot) in the shape of bullets. They load in a manner similar to metallic reloading. I picked a third method, “sizing a cartridge into a bottleneck style brass.” To do this, I used three different die sets: a .45 ACP sizing die, a carbide .40/10mm sizing die for the necked-down portion and a .357 SIG sizing die to form the “nose” of the shell.
Changing the size of a case from .45 to .40 requires pretty malleable brass. The brass needs to be annealed, which means heating it and letting it cool. Once I cut it, I used a propane torch to heat the neck until it changed color. For the cut down .308, it took about 10 seconds on each side with a propane torch. After heating, just let the brass cool to room temperature.
I cut the brass a little oversized, then trimmed it evenly using my Frankford Arsenal case prep tool. I wanted the cases to be completely concentric and square before I chamfered the inside and outside of the case mouth.
I put the chamfered brass into a .40/10mm carbide die and used a generous swab of Hornady Unique case lube to prevent collapsing the case. Originally, I used a Sharpie line on the brass to gauge how far to neck it down. I found the best way was to adjust the dies to the upper limit of the press.
I wanted to have the shot column as long as possible, so I cut the brass as long as possible. I cut it to 1.285″ on the lathe. It really turned out to be a rough cut, until I trimmed to 1.280″. Later, when I used the .357 SIG sizing die to create the nose of the shell, I tried to get the OAL as close to 1.254″ as possible. There was a balance between getting all 120 grains of shot in and getting the shell (not cartridge!) to fit in a standard .45 ACP magazine.
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