Myself, I would address the leading problem.
#1) Use a bullet sized to groove diameter -.002" over groove diameter. Example: .308 Winchester/ use ..310"-.311" bullets.
#2) Don't use super hard bullets (everybody loves selling hard bullets), unless you're shooting a plain based bullet at very high velocities.
#3) Use a gas checked bullet if you're pushing a bullet over ~1200 fps. I've never found that I needed very hard bullets with gas checks, I use wheelweights + a little 95/5 solder for my 30-30 loads, and they hit 2250 fps.
Now, to get the lead that is presently in your barrel.... Find the all copper pot/pan scrubbers in your grocery store called "Chore Boy", cut off a small piece and wrap it around an old, worn out bore brush of the appropriate caliber, and scrub away with your favorite solvent. The Chore Boy really makes a difference, doesn't harm your bore at all, and is dirt cheap. Follow these tips, and lead fouling will be a thing of the past! Good luck!