If you are a Reloader 158 grain RNL Dardas brand bullets over 3.4 grains of Titegroup works for me. Its a mild load and I like the RNL shape better than the SWC or the WC as they tend to lead up less. I'd start with the .358" diameter and adjust up or down after shooting a bunch. .358" is usually the standard for reloading but slugging your barrel is also a good idea.

If you do NOT Reload I'd go with Federal's American Eagle standard velocity 158 grain RN or SWC lead. If you are going to be a frequent shooter I'd STRONGLY SUGGEST visiting Dillon Precisions web site, drink the BLUE koolaide and get yourself a reloading Outfit. For low volumes the Square Deal is good, but if you are young and going to get into this hobby in a big way, I'd suggest the Dillon 650. IMHO it's the NUTZ of Reloading presses. The 650 also uses standard dies (unlike the SD-B which uses proprietary dies).