Bump fire stocks are basically poor man's full autos. The Slide Fire solution seems to be the kid on the block, but F&W has recently developed an aluminum version of a bump fire stock. Check out their official copy:
This AR-15 Select Fire Stock kit for in black aluminum system that retails for $359.00. THIS KIT MUST BE ASSEMBLED. Bump firing is the act of using the recoil of a firearm to fire multiple shots in rapid succession. This process involves holding the foregrip with the non-trigger hand, releasing the grip on the firing hand (leaving the trigger finger in its normal position in front of the trigger), pushing the rifle forward in order to apply pressure on the trigger finger from the trigger, and keeping the trigger finger stationary. The firearm will recoil and then return to its previous position after the round has been fired first resetting and then pressing forward against the trigger thereby firing successive shots. The relatively-rapid bursts from semi-automatic firearms crudely simulate the discharge of automatic firearms. Even though a large number of rounds are fired in rapid succession, the trigger finger initiates each discharge; therefore, fully automatic fire is not actually taking place.
While this doesn't seem to have the professional flare of Slide Fire, it does look like fair competitor. $360 seems a bit high for a kit that you still need to finish at home. The best part of the Aluminum Bump Fire Stock is the commercial. I love the great state of Texas (no income tax, shall issue CCW, super easy to get a suppressor, epic bbq, etc.) but this commercial really looks like something that you would see on Texas public access TV. A dude literally wearing overalls goes full auto on a lake! LOL, I also like at 50 seconds there is a scene where the AK either doesn't feed, or the mag is empty, and it doesn't get edited out! The scrolling phone number and looks of satisfied customers really make this vid great.
You can pick up the kit at F&W with options for AK, Saiga, SKS, AR-10, AR-15, and Mini 14/30.