Any firearm that fires more than one bullet when you pull the trigger is considered a “Machine Gun” under US law. It doesn’t matter if it fires in bursts, if its full auto, or even if it fires out of multiple barrels. People are always looking for different ways to get around this restriction and increase your rate of fire, without actually turning into a “Machine Gun” and having its sale restricted. One of the more popular items are bump fire stocks. A new contender is the bi-directional trigger by Liberty Gun Works.
With their bi-directional trigger, you fire once when you pull the trigger, and once again when you release. Since it only fires once when you pull the trigger, and there is no mention in any laws about firing when you release the trigger, it’s able to be sold without any of the hassle you find with machine gun sales.
That said, it’s an incredibly stupid, unsafe, and irresponsible firing mechanism. With this, you don’t have the option of only firing one bullet. You pull the trigger once, and you better have some where safe to fire that second bullet, because the second your finger slips off the trigger, you’re firing again. The only way to stop the second shot would be to try to unload the weapon, which again, would require keeping one finger firmly depressing the trigger.
Fire once and then see someone down range, you’re stuck holding that trigger until the range clears.
There is no option to turn this feature off. It only has the one firing option. When you pull the trigger, it takes away your ability to decide NOT to fire a second shot.
If, for some reason, you want to pay three times as much for a rifle that has been modified in an unsafe way, you can swing over to their website and order one.