I bought this rifle a month ago.
Had nothing but problems with it.
Took it appart and gave it a full clean and tuned the action.
Runs like a dream now.
But fair warning. If you are not the technical type just return it and hope they send you a better one.
And yes, its tunable. You could even slow down the rate of fire if you wanted to. It runs on a gas operated piston that pushes a rod to a "gear box" to cycle it. Simply change the gear ratio with some custom gears if you wanted to.
And fear warning. The screws that hold the covers in place on both sides of the gun are made of some kind of black butter or something. Terrible quality and stripped clean with little effort
I replaced them when Stainless steal allen key screws right away.
My 777 .30 is now fully tuned to perfection and spits out fx hybrid slugs at 1050 fps
If you think this cant be done Please dont even comment on this. Because it can be done.