Bore Butter works, ... except here in the Mojave. Opened up the tube to slosh the arbor of the 1860 last Saturday and it was as thin as water. Probably not helpful that it's 120 in the shade though.
Any hot weather suggestions for a substitute?
I'd figure you could just mix some beeswax with your BB and stiffen it up a bit. Beeswax melts at 144-147°F. Or paraffin, if you have it. (Paraffin melts at 120-160° depending on what kind you get though, be sure it's the harder kind.)
Crayons work too, and they're kinda pretty mixed into my smokeless lube.