Hey guys, Thought I'd ask a question here since I'm stumped on it. A customer came into my shop the other day asking about a "Porcelain Reinforced Barrel" for his 9mm. I've heard the rumors about the Govt. testing these for the large caliber weapons on gunships to prevent the barrel from overheating and warping. They also claim that it can give an increase to muzzle velocity by up to 30% over a traditional steel barrel. But do they really exist for small caliber firearms?