Second Swaging Accessory

I’m focusing first on swaging accessories; the second piece in my “set” of items I want to design and print finished up overnight.  This is a ‘derim cup’.

Derim Cup Assembly

Derim Cup Assembly

A derim die takes a piece of empty .22LR brass, and pushes it through the die to flatten out the lip.  That creates the jacket for a .224 (for .223 / 5.56) bullet.

The derim cup catches the jackets after they’ve passed through the die.  This is a problem that can be solved many ways – using an empty soda bottle or hose, for example.  But why do that when I can print one, and it matches my press?

The whole assembly comes off the die easily and separates at the base so the cup can be emptied.  This one is sized to contain my typical batch of jackets that will go on together for further processing.


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