Knockout Brass Breech bases
thingiverse
Update: 12/20 Redesigned the barrel piece to accommodate exactly 9/16 inches of brass. A cutting guide for 17/32 inches of brass has been added. The NStrike attachment has been updated with a new design and reuploaded. Update 12/16 Increased the length of the barrel piece and attached an NStrike attachment obtained from https://www.thingiverse.com/thing:3427635 These designs aim to simplify modifying knockouts. Hopefully, they will prove useful for you as well.
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With this file you will be able to print Knockout Brass Breech bases with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on Knockout Brass Breech bases.