Thunderbolts = leaded barrel.

[pitpawten]

Slightly OT but mercury was mentioned above and got me remembering this site for all things chem/sciencey: http://unitednuclear.com

 

[Mark K]

I generally prefer solvents for cleaning and lubricants for lube; I'm not a fan of the combination CLP products, although I do use CLP in the field. Mark K, your experience with CLP intrigues me (I somehow missed your #57 when reading through the thread earlier).
Based on the results posted at:
https://www.youtube.com/watch?v=WdYWQfbC5Og, I wouldn't expect CLP to have a chemical advantage on lead. Possibly due to different manufacturers' CLP formulations, possibly due to penetrating under the lead...

Please don't think I'm an expert at this stuff. I'm not OCD (much) about my firearms, and the primary reason I use CLP is that's what the Army issued me back in the 80's. That, and I do like the convenience of a single-step cleaning and lubricating chemical -- the separate solvent and oil that the Army issued before CLP were a pain in the ass. Yes, I know that a jack-of-all-trades is a master of none.

I used CLP to soak my 1911-22 barrel really out of desperation. The lead was so caked in the bore, that by looking through it I thought at first (and at second) that the bore was completely physically chewed up somehow. I literally couldn't get a bore brush through it more than an inch or so.

I'm just saying that the CLP worked. Something different might well work better. But whatever you use, I think the secret is the long soaking.

I'd definitely try that before going to potentially more-hazardous chemicals.