I used to use Shooters choice lead remover.
www .wholesalesports.com/storefront/hunting/gun-maintenance/firearm-cleaning/lead-remover/prod79539.html
I put some on a nylon brush and run it through once, wait 2 to 5 min, and the run through a brass brush. Cleans it right up! Normal cleaning from there.
One thing that I was told about (by a bullseye shooter at my club as well as the gunsmith at my local g-store) JB Bore cleaning compound.
www .brownells.com/.aspx/pid=1160/Product/J_B_reg__NON_EMBEDDING_BORE_CLEANING_COMPOUND
What you do is spend about 1 hr at the bench (at home) lightly coating the lead bullets (on loaded rounds) with the compound. I found the best way was to dip the bullet head in the paste and wipe off the excess with your finger.
Once you have about 200 done go to the range and put 3 groups of ten "treated" rounds down range. Then follow the instructions on the container of JB to clean the barrel. repeat untill you have fired about 150 rnds of the "treated" ammo.
Now fire every second round (one treated one not etc.) untill you have 25 treated rounds left. (follow cleaning instructions)
Now fire every fifth round treated (I found it easier to load the treated round in the mag first, then 4 non-treated rounds, then a treated one and then 4 more non-treated)
Do this untill you are out of treated rounds.
All told this is 350 rnds, it doesn't seem to make a differance if you treat more rounds with the JB, but it won't hurt either.
The first pistol I did this with was my M&P9 (I was having a hell of a time with leading in my barrel) After I did this the barrel is very shiney, I never have to spend time cleaning out the lead (leading in the barrel is a thing of the past) and the best part...... My groups at 25yrds went down from 10-12" to 4-6"......
I for one LOVE JB Bore compound!
The only downside...... now you have to take apart your mags and clean them or else they will start gumming up from the compound residue in the mags. and you don't want to use your reloaded ammo boxes for this either..... they are a chore to clean out as well.
YMMV Cheers and good luck!