Been using a 50-50 mix of it and bees wax since 1996, a logical choice I thought since it has a higher melting point than most tallow. An informal test of it came when a friend left a box of bullets I gave him in the locked cab of his pick-up for 3 days in July in Newbrassky. Yep, still in the grooves when he discovered his
test mistake.
Been using the stuff since the 80's as a hand lotion, back when I painted for a living, makes a good boot grease and lip balm also.
A couple of things on rendering it, never let it get hot enough to smoke, breaks the stuff down. You can use water when you render and skim it off, but put it back in a pot and put a candy themometer in it and bring it to 250 and hold it there for about 15 minutes and all the water will boil out, water in it will make it go rancid.
I then strain it through a muslin bag to get the tissue out of it.
Had a heal crack a week or so ago, got under the loading bench and got out one of my coffee cans of it, stuff rendered in 2000. Nope, not rancid at all, smells like fresh deer tallow. Put some in the crack which is all better now. Would have put it on my lips except they wern't chapped.