I ended practice for my high school rifle team a bit early today.  I had them kill the lights in the indoor range we use and loaded up my m4 that has a phantom flash hider on it.  Turned on the aimpoint and fired away at the 30m target.  Hardly any light signature at all came from the carbine.  All you saw was a small glow right around the tip of the barrel.  No flame shot out for 2 feet or anything like that.   on my next rifle i will go with the vortex and see if its any better.  
After reading all the comments here about the phantom vs vortex im very happy that my results were better than I expected.  Ill try again next thursday and get some digital pictures to show how little flash there is

Shooting in the dark is cool.

I enjoyed night firing when I was at Ft Jackson.

I have found that the Norinco yellow box, case marked CJ 93, will have a 2' flame out of a 16" HBAR, and a 3x2' flame out of a 11.5/5.5" CAR. All on an 80+ degree day, at noon. It would be moronic to use this ammo at night in a defensive situation.

Very impressive for onlookers, but not practical. Too bad I'm about out.

What ammo were you using?

ss109 green tipped.  Im going to try with some m193 and some q313a the next time

also had my first low light experience yesterday. using Lake City on a 20" Hbar, i was throughly impressed as a bystander but when it got even darker the flash was really bright through the scope i was using way cool.

Same exact experience with a phantom and 11.5 inch barrel, I was very impressed. I was expecting to be blinded, but it was little more than someone taking a drag from a cigarette.

The Phantom has the same muzzle signature with pretty much any ammo from low flash Black Hills .223 to hot M193.  End result is always a dim glow at the tip of the flash hider.

where do you goto school?