About the only thing I shoot in .38s is the 158gr SWC (although I did just pick up a 125gr RNFP to try out). I get great accuracy and reasonable velocity.
The biggest factor in barrel leading is fit. If you have a properly fitting bullet, you can push cast bullets to the pressure maximums and still not have any noticeable leading. The key is to get your bullets sized to .001-.0015 over groove diameter for your gun. Each gun is different and bore diameters do vary. Get a good fit and you can push a pure lead bullet to over 1000 fps without leading.
The next biggest factors are bullet hardness and bullet lube. Too soft a bullet for the pressures obtained will cause leading. Too hard a bullet can also cause leading where it doesn't allow for engraving of the rifling and just strips the lead as it goes down the barrel. I don't know much about the different lubes other than what works for me. Where I cast and size my own bullets, I tumble lube them in a lube made up of Johnsons Paste Wax / Lee Liquid Alox / Mineral Spirits in proportions of 45/45/10 respectively.
Different powders will also contribute to leading, but I find that mostly the case with shooting cast bullets in rifles.
Good luck, be safe, and happy shooting!