Most of my life I have shot .45s, .22s, .380s and .38/.357s. All but the .38/.357s have been in semi-automatics weapons. Just recently a bought a M&P 9mm Pro with the main reason being the attractive prices on the 9mm ammo, both 115 grain and 124 grain. I usually buy Remington, Winchester and Federal to shoot at the range. When I go to clean by gun, I'm amazed at how dirty it is. There are plenty of thick black deposits of soot and powder inside the gun and I can't every remember that being the case with other calibers so I started thinking, maybe that's why 9mm is less expensive that the others, the manufactures can get by using cheaper powder. I mean you would think .380s would be cheaper as they use less powder and the bullet is smaller so there has to be some reason behind his. Has anyone else noticed this or am I the only one? Let me know. Thanks, Jim