These are .stl files of bump fire devices for AR-15, AK-47, and Saiga-12 that fit onto the grip of your rifle. Also a BMF activator crank fire design.

Test Videos:

These files were taken down by the industrial cock inhalers at Thingiverse and Grabcad. Feel free to mirror, spread, and modify these files. Also fuck the NRA

-3D Bump