At least for myself at the moment. I started making my own priming compound and realized that I needed cups to put it in to act as whole caps. I designed a punch that works pretty well at stamping out .006 brass shimstock for the purpose but figured there had to be a better way. Thought of this a few nights ago and designed caps with the 3D printer. They work fantastic. Perfect seal, fit and break alot like metal caps when fired. And they absolutely don't jam up the action at all. I can print ALOT in a short time.
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