doublebarrel,
Use a bronze or brass brush to clean the leading out of the frame where it looks like flame cutting. Use CLP to soak the leading with. Use a really wet tipped Q-tip or cotton swab to soak it. Let it soak fro 4 or 5 minutes and then brush it away. It may take a couple 2 or 3 tries to get it all off, but it will work to remove any leading.
After all the gunpowder and lead or removed you'll know if you're having any issue with flame cutting. A little flame cutting won't hurt anything and it usually stops after a few trips to the range. Flame cutting is caused from hot gunpowder burning outside of the casing, and flashing thru the cylinder gap. You might need to switch ammo if it continues to be problematic.
I tell just about everybody to try using a more expensive .22 ammo like the CCI Mini Mags. If you're only going to use it for target practice or plinking you might like using CCI CB shorts (just a thought). It'll cost more to shoot quality ammo, but many of the problems a resolved by shooting it too. Even good quality .22 ammo is cheap in the long run, so why not treat yourself to the best available. It usually helps with accuracy as well.
