I would have never thought that a Performance Center pistol would have such a variation in barrel sizes. Everyone I talked with said they were using 9mm, no issues? Well, with a lot of digging for references on revolvers, I couldn't find very much. I did come across one u-tube video of a gentleman explaining on how you should select the proper bullets for a revolver. The cylinder has a chamber and a throat, and when the bullet leaves the cylinder, it goes into the forcing cone and then exits the barrel. I was trying to use 9mm bullets, .356 dia, and not having much luck with accuracy, consistency, and overall dirtiness of the pistol. After I watched the mans video, I'm now using 38/.357 bullets, Blue Bullets, and everything has gotten better. The bullets fit the chamber, are reduced by the throat, and final size is reduced by the forcing cone, This controls gases from escaping passed the bullets as they transition through the pistol. This has greatly increased accuracy, consistency, and dirt. This has also reduced bullets from walking out of the cases from recoil, not completely, but what I can tolerate. Just so you get an idea, my .357 bullets come out the end of my barrel at .354 dia. Hope I didn't add confusion to the story, mic the throats of your pistol and choose bullets accordingly.