Frostbite, HammerHead is a barrel company, not paintballs.
Call To Arms, they say that it's because their barrels are "reverse porting and precision rifling". I'm not a machinesmith by any means so I don't know if that's the real reason. All I know, is that countless people in the region that I play in swear by the barrels. They're accurate and dampen the sounds of the marker shooting slightly. Don't dampen the sound to a large degree, but to a small amount. They make barrels for the A-5, Phantom, Cocker, Angel, Matrix, Intimidator, Automag, Spyder, Tippman 98 and the Ion.
No matter which barrel you buy, you can buy the fin/back for multiple markers so that way you don't have to get the several copies of one barrel for different markers.
I recommend HH barrels, but of course I'm biased because I've been told about them since I started paintball.
Sorry if this sounds like a sales pitch guys. Not what I was meaning ta do.
http://www.hammerheadpaintball.com/barrels.htmlThe Joker