I hope those are empty beer kegs.
Well, not exactly. It was still pressurized. We were at an old landfill. Damn thing blew the leaves off of trees 50 feet away. Smelled like a brewery downwind.
We also found out (at the same place but on a different occasion) that 50 BMG tracer rounds, will, indeed, start a brush fire. One round hit the hill, deflected, made a beautiful arc up and landed behind the hill. The hill was over a quarter mile from us. The round came to rest somewhere "beyond". (I wasn't the shooter on that one, I was spotting for a friend who owned an AR50 upper).
About 5 minutes later, I see a thin white trail of smoke coming up the other side of the hill. I pointed it out and we all jumped in to my truck. The area it was coming from was inaccessible to 4WD - I drove as close as I could get us, then we all jumped out, and ran another half mile to where the fire was.
By then it had spread in to a rough 16 foot circle. The grass was above waist height there, so some of the flames were taller than I was. The middle area was burned out already - it was just spreading slowly, leaving bare ground behind.
I jumped in and started stomping on the grass. My friends stood there watching in disbelief, until I yelled at them to help. Stomp a few times, move to clean air, breathe, hold breath, go back and stomp a few more times, go to clean air, repeat...
We knocked out the fire. Couple of scorched pant legs, but it didn't spread out of control.
Anyway, now we only shoot tracers when it's raining or there's snow cover.
We also haven't shot any more beer kegs. Propane tanks, yes, but no more beer kegs. Too expensive, and quite a waste.