Speaking as a person who actually did set the grass on fire at the Boulder Rifle Club, maybe you should hunt with a conical or camera this year. We are facing the same conditions out in NW Colorado.
In the event referenced, I was trying olive oil as a patch lube. Fired my first shot, then stepped back and turned away to load again. Suddenly smelled smoke! Looking down range there was a yard-wide circle of flame! Managed to stomp it out, and heart rate slowed down after a few minutes. Fired three more with olive oil lubed patches, walking down range after each. All three were smoldering. End of experiment.
I later learned that olive oil has a low ignition temperature. Peanut oil has the highest ignition temp of commonly available vegetable oils. In the end, however, I still lube with a mix of lamb fat and beeswax.