Tires work really WELL,....but one has to watch out for a buildup of unburned powder that WILL eventually flash, and make life exciting (and warm).
I would NOT shoot BP through a tire baffle system,....
Holes in the bottom of the tires and periodic rinsing with H2O would seem to be one way to defeat the unburned powder gremlin.
Lotta' guys talk about putting insulation in the tires,....I never bothered, and found 8 feet of 20" truck tires wired together to really quieten down my shooting.
GTC