I just bought a 12" SpecOps (Stiffi) Blackcell C barrel and I'm very pleased with it. It's very light, a little quieter, and supposedly "self cleans" if a ball breaks. I've put almost two cases through mine with good accuracy and no ball breaks.

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Armorer Info: SpecOps A5A2, E-Grip, EndGame 10" Barrel, 12" Blackcell C Barrel, JCS Red Hot Powertube, 68/4500 Pure Energy HPA, PSI SS Braided and 32 Deg Coiled Remote Lines.