Re: .308 Flash Supressor
Smith Enterprises Vortex....I use one on my .30-06.
Very Very effective. I shoot at night very often and there is absolutely no visible flash to the shooter. I don't use Night vision scopes, so I couldn't tell you what that would look like.
In complete dark from the profile the flash is less than a .22 mag which is about the size of quarter at the muzzle and it looks like a battery operated flashlight right before it goes completely dead. Very dim but just noticeable.
I don't have another one to compare to, but this one worked out very well for my uses.