What is the flash like from an AK brake from a 14.5" M4 barrel compared to other brakes.  I'm specifically interested in the 14.5" barrel.  But I would also like to hear comparisions from 16" barrels if you have experience.

The AK brake will produce a fairly noticeable flash, especially if you use ammo without a flash reducer in the powder. The Smith compensator will generate a flash you gotta see to believe!(about the size of a basketball in diameter, and 3 ft long)

I have a Bushy AK-shorty, and it is an impressive blast. At night it throws a foot-long flame out the front, complete with sparks, and throws 7 inch flames out the sides. I would warn against the AK style brake for a reason not cited hear much: Noise. It is the loudest and most eficient brake I have ever seen. I can keep iron sights on target at 100 meters offhand round after round. It is also louder than a .308 hunting rifle. As entertaining as it is to knock CLP bottles over in the lane next to you, it is the last weapon I will choose for home defense. I fired it ONCE without hearing protection outside and almost dropped the rifle it hurt so bad. This is from someone who didn't think it was a big deal to not wear hearing protection at the qualifying range with an M16A2. It is deafening, and you most assuredly will have acoustical superiority over your enemy.

yeah, all muzzle brakes are pretty loud. The smith brake does a great job of keeping the muzzle down, but at the price of the flash & noise.

Regarding OFFLINE'S comment, are any brakes noticeably louder than others?  Like how does the ak compare to the ycomp to the smith?

I have heard that the Y-comp is louder than the others. The AK, and the Smith brake were about equal, to my ears, anyway.

offline - I too have a shorty AK Bushmaster, and w/most ammo it's blast is much like you stated. However, if you REALLY want to see fire, I have some of the old Norinco .223 w/'93 headstamp, and it absolutely will give you a ball of fire about 4 feet in diameter. I once rapid fired 30 rounds after dark downrange and
I saw spots for about an hour. The Norinco ammo has one HECK of a flash! I guess the Chinese dont know what flash-retardant powder is!

Resantly shot both the AK brake and the Armalite brake side by side.
The Armalite brake was better at recoil control and the AK brake seemed louder, also the AK brake had more flash to the sides even though my buddy next to me said the blast to him was worse with the Armalite brake.
Both were 14.5 & 16" carbines.