Yes, I've used regular Turtle Wax in my untreated corncob grit. It works very well, and the microscopic wax layer preserves the shine for months in storage. Just add an ounce or so to the corncob in a Midway tumbler, then allow it to run a few minutes to spread the liquid out a bit so it doesn't get clots on the brass.
For several years now, I've been buying Turtle Wax "Scratch and Swirl Remover" for the same job, in the pious hope that it might be a tad more aggressive in action than the regular stuff. The shine is almost unbelievable...FAR brighter than factory-new brass, and again, it keeps the shine for months or years in storage before reloading. Still, the standard TW works fine, too. Don't be afraid to run the tumbler for several hours or more.
No brass deterioration has appeared from the use of these products, and I do a LOT of cast-bullet loading per year.