My only good story on shooting reactive targets involves an old antifreeze jug full of water, and my dearly departed MAK90 (not dead, just sold to a good home when I got my Mini-14).
While the MAK would keep shooting no matter how filthy it was (true to it’s AK heritage), it was notoriously inaccurate. A friend and I set the jug out way too far away, inspired by earlier good results with some customized .22’s, and got tired trying to hit this jug offhand at 200 yards. We walked over to see if there were ANY holes in it, and at about 10 yards I hip shot it with one of those cheap Russian HP’s you see everywhere in the little white cube boxes. I was surprised later to find that the disappointing little entry hole was backed by a 10 inch exit hole, on a jug that was only about 3 inches thick. I was more surprised with a more immediate reaction from the water in the jug, which flew back in my face. I will NEVER fill a reactive target with water from a stock tank again! Bleah!
Actually, I think that’s the difference between (can’t remember if this is the right terminology) high-order and low-order explosives. Low-order explosives, such as gunpowder, burn at an advanced rate. High-order explosives, such as nitroglycerin, literally explode, rather than merely oxydizing.
I’m a bit curious about that too. On the one hand, the “cream” is just sitting in the can in a puddle, and gas bleeds into it when the nozzle is opened, so it might just leave a big splat while the gas blows the can apart, on the other hand, I may be missing something. I know from experience that sealed cans of carbonated drinks can be fairly dramatic, though I haven’t tried a wide variety of ammo on them.
Since people are quoting me, or at least referring to something I wrote, this is what I was trying to say: Smokeless powder (nitrocellulose powder?) burns rapidly, rather than explodes. Given Anthracite’s definition involving the speed of sound, I don’t know if all smokeless powder burns at a subsonic rate.
But that was just an aside to my original message: that a force equal to and in the opposite direction of the force propelling the projectile overcomes the mass and inertia of the bolt in a blowback-operated semi-automatic firearm.
Spray paint is quite entertaining as well. I shot a can of spray paint dead center, and the can blew itself in half. the bottom half didn’t move noticeably, and we never were able to find the top half. The sand at ground zero was all blown away and all that was left was the hardpacked dirt underneath. The paint left a blackened “blast pattern” on the ground, spreading radially from the can. It actually looked like somebody had set off a small bomb.
