http://www.mastercastbullets.com/ Mike have been very helpful with me.
Pumping up Vel's will cause leading generally at Velosities over 1000 FPS -- at least for me in my S&W 586 .357. This is easily taken care of by using a couple of strands of Chore Boy copper strands taken from a pad and wrapped around your brass bore cleaner. Mike suggested and it works.
I buy bullets from Mike too and have been very happy with them. Use 158 grain SWC or RNFP and you should be able to run them with full-power magnum loads using a middle-speed powder like Herco or AA#7
without much leading. I haven't tried really running up the velocity with max loads of W296 or 2400 yet, or shooting them from a carbine. They might need a thin coating of liquid Alox lube added (in addition to their hard wax lube) for that.
I've also been casting my own bullets; lately I've been shooting a lot of 148 grain DEWC's loaded with 7.0 grains of WSF powder. That's maybe a .357 Sig equivalent load -- a big step up from .38 Special and a small step down from most .357 Magnum loads. Cheap to load and lots of fun to shoot.