Still using the good old NRA Alox-Beeswax formula applied with the lubricator-sizer, no need for heating. Works as well as anything. Yes, a little smoke when used on the indoor range, but no objectionable odor I've ever noticed.
Even with centerfire rifles at 2000FPS-plus the lubrication is plenty adequate, usually leaves a little star-shape residue on the muzzle.
I use a couple of antique rifles in obsolete calibers (.45-90, .45 Sharps Express, .33 Winchester) with cast bullets in small quantities, for which I don't want to mess around with lubri-sizer, so I apply pure white lithium grease with my fingers, filling the lube grooves. Probably one of the best bullet lubes that exists, and a few dollars per tube at the auto parts store (I've been using the same small tube for years).