I have only used it in the 22 Hornet, 2 different single shots. I have had bad experience with it. It was not heat however. I got blown primers, flattened primers, 400 fps swings in velocity all with a load that was a middle of the road load that gives low pressure? This was with both rifles. After trying very hard to get it to work, I gave up. I am now very leery of using it in anything else. I am now using W296 with a 34 grain bullet and a small pistol primer, that gives me a low pressure round with higher velocity (around 3050 fps) than any Lil'Gun load can give me. It is a beginning load in the Speer 14th edition load manual. I know that others swear by it and I do not know what I did different, but never again! Remember, this powder was developed for the 410 shotgun and adopted for small capacity rifle rounds and magnum handgun rounds. People having different experiences with it does not surprise me, due to my personal experience that differs from many others.
Good Shooting and Good Luck