Joe
How do you anneal a loaded ctg?
Tom
I don't! Pull the bullet, dump the powder and be VERY fast in the heating of the neck. VERY fast! Then, with the decapping pin removed, resize the case if necessary and reload the dumped powder and bullet.
I DO NOT recommend annealing primed cases but have done it myself many times. Have had only one primer pop and that was my first 22 Hornet, it proved to be quite a stimulus to proceed faster with the heating! The heat transfer speed with the smaller cases means the operator has much less time before the head becomes too hot. Needless to say, any case that pops a primer should be discarded.
Using this method I've repeatedly sized 30-30s down to 219 Zipper Improved, shot them for years in the Improved chamber and then sized them BACK down to standard Zipper (later, for another rifle) with absolutely no case loss whatever.
Good luck and regards, Joe