Briman

Yeah, I've had the opurtunity to shoot propane cylinders, after they changed that valve configuration a few years ago we ended up with some extras. A Mini 14 and .223s didn't ignite any of them, too bad, we were looking for some fireworks...Gas tanks rarely go up unless the bullet makes a spark on something or is a tracer round. It's the fumes in the tankthat ignite the easiest.

I'm not sure what causes that black ring but looking at some targets I have on file, pointed lead bullets leave much more than jacketed.

Doug