Bubbled Paint?

After the last club launch I thought there were only two minor repairs. I looked a little closer at my GBU-24 Paveway III. There was a nickel sized blister in the paint!
BT-55 tubing is fairly thick, I didn't know what could have caused it.

Looking into the tube I saw there was some wadding still inside. From the engine end I blew the wadding out.

Apparently it was still smoldering after ejection, long enough to heat up and blister the finish. Crap! The wadding is flame resistant crepe paper, it's never been a problem before.
No re-finish on this one. I'm afraid the body tube is pretty thin under the bubble.