From Len Savage via email:
A forced reset trigger does exactly what it sounds. It forces the trigger to reset.
So when you pull the trigger, there is a cam (compared to traditional AR triggers) that pushes your trigger forward, back to the ‘start’ position which allows you to fire your subsequent shots much quicker. The cam also will not let you pull the trigger until a fresh round of ammo is chambered and ready to fire. Once it chambers a fresh round the cam then drops away and you can only then pull the trigger.
With a forced reset trigger you have essentially taken semi automatic method of fire to near 100% efficiency (not unlike a bump stock in that regard). By forcing the reset and limiting the trigger travel there is an economy of time and movement that allows for a rate of fire near that of the host firearm cyclic rate.
It’s not a machine gun because you are pulling the trigger once for every shot fired. You are doing it. You are doing it with incredible speed because there is no waste of time or movement.
Incredible fire rate sound like fun? It certainly is!
Reason for me blasting it out is I keep getting asked about them.
I have hands on technical experience with them.
Currently they are ALL legal (and have been since July 24th) unless Judge Reed O’Connor gets overruled.