The bullets are not silent, they are fibbing. They really fib when they claim they have a 235gr bullet that is silent when fired and has 2-3 times the energy of the conventional round it substitutes for. IOW the whole claim is do do. All they show looks more like a rocket projectile and it's not silent as with other rockets. It must have a higher velocity to get the E and if it does, it's going to sound very similar and definitely not silent.
The bullets are not silent, they are fibbing. They really fib when they claim they have a 235gr bullet that is silent when fired and has 2-3 times the energy of the conventional round it substitutes for. IOW the whole claim is do do. All they show looks more like a rocket projectile and it's not silent as with other rockets. It must have a higher velocity to get the E and if it does, it's going to sound very similar and definitely not silent. This thing works on the "pinball machine" principle. A piston flies forward and whacks the rear of the projectile, sending it down the barrel. Given the force of that shove and the weight of the projectile, it could pack quite a bit of energy and be nearly silent.
There is no propellant in the projectile, therefore no rocket-like sound. A relatively heavy bullet is used in order to capture useable energy from the design. It really does produce no flash, since the gunpowder detonation is contained in the case. Small Arms Review magazine had an article about this ammo, and the fact that each round would technically be subject to BATF's regulations concerning sound suppressors.
It has nothing to do with the MD shooter, though... wrong caliber. A 235-grain .224" diameter bullet would be about two inches long!