Don't give up on cast bullets!
Don't give up on cast bullets! I picked up a tip that I've used successfully in ALL of my revolvers and pistols at one time or another.
Get yourself some "Chore Boy" copper scouring pads from your local Ace Hardware (mine carries them, you can also buy them on Ebay). CAUTION: If you buy another brand, use a magnet to ensure that they are copper and not copper-plated steel!
Pull some strands of the copper Chore Boy from the pad (you may need to use your "shop" scissors to cut them) and wrap it on brass brush. Experiment here, you want a snug fit in the barrel, but not so tight that you need a pliers to pull the cleaning rod out. Run the brush back and forth through the barrel about 10-20 times. The lead will be gone.
I also use this method in the cylinders of my revolvers, only I chuck a straight cleaning rod in my battery powered drill at low speed, and run the brush with the Chore Boy in each chamber for 30 seconds, slowly working it back and forth in the throat area.
In less than two minutes, your gun is totally free of lead, with NO harm to it.
If you choose to pursue and correct the cause behind the leading, by all means do so. I have done that as well. But whenever I get the occasional lead deposits, for whatever reason, they're gone in minutes. And I continue to enjoy the economy of cast bullets in all my handguns.
Good luck,
Lou