another full auto machine gun mechanism
You may have seen this already on the comment on https://www.instructables.com/id/8-SHOT-KNEX-HAND-GUN-REVOLVER/?&sort=NEWEST&limit=50&offset=50
The comment with it was posted May 7, 2008. 12:25 PM.
Basicaly the hammer is attached to a small cog, a motor or handle is attached to a cog with only 4 teeth(on each half) the 4 teeth will crank the hammer back then when it runs out of teeth it will snap back, it actually works(I would have posted but my sister destroyed it D= ) te only problem I had was the mag, I attempted to build a box mag, oh and the fact you need a metal rod for the handle/motor and for the hammer with gear on(I lost 3 red rods because it just twisted the hell out of them, it was impossible to use them again)
So you can only make it with some sort of renforced rod, but overall it actually works.
this is just a small step by step type thing
sand down 3/4 of a small cog.
to speed up rate of fire add speed up gears (optional)
make hammer, lock canibalised cog onto a rod with hammer
connect it to speed up gear/s
add elastic band to hammer
add mag, clip or belt. note: if you make belt the add timmed gears to the speed up gear.