Re: How does a flash hider hide muzzle flash?
The key to gathering information within a scientific perspective is by asking the right questions...
Anything that you stick on the end of a barrel will have some effect on muzzle flash, but unlike the traditional M-14 F/H that creates a sort of expansion chamber at the end of the barrel that reduces the amount of gas that burns, I am not sure that the vortex design actually hides muzzle flash so much if you actually measure the luminosity output...nor does the M-16 f/h for that matter.
What it does, and what they both do, is to disrupt the tendency of hot powder gas to freely bloom at the end of the muzzle into a big ass ball of flame. They do this by redirecting the escaping gas away from the shooters line of sight so that the dude pulling the trigger is not temporarily blinded by the light.
Redirecting and suppression are two different questions, and the vortex is the best choice for that dude pulling the trigger, especially when using night vision, because it produces a focused output...sort of a longer and much thinner flame....it makes a big difference as to what the shooter is still able to see after firing a few rounds.
What works is what matters most...I'd say it might reduce visible light to the shooter's eye by 95% or more...the dude getting shot at maybe not so much...but a little night time trigger pulling will tell the tale.
TC