@sinfulsaint:
I have tried three kinds of reactive targets:
1. aluminum pop cans (e.g., Coke & 7up): These work with everything, from 22 to 58 caliber muzzleloader. We save them to recycle and take them out for targets when we go. Drilling them repeatedly doesn't alter the recycling value!
2. clay targets: These also work well for just about anything. Most of the ranges I have shot at will have them laying around on the skeet & trap grounds, and a number of whole ones can be obtained from the misses. These can be used for shotgun if one is available. The larger chunks can be used for rifle & handgun, (and air guns too, I'm sure) giving a satisfying reaction to being hit. One drawback: swine like to eat the pieces, which will kill them. One has to be careful where they are used.
3. plastic milk jugs, filled with water: These give a nice effect with more powerful guns, but not the smaller ones. They are nasty things for the environment, but shooting them doesn't change this for better or worse. Blasting them is great fun with larger guns.
4. Aerosol cans: Even when empty, these can be interesting and, if partly full, somewhat exciting. Your action will be better on a hot day. (good old gas laws!) Being chased by a flying can is interesting, so be careful to keep your guns safe -- semi autos are not when you are running away from the flying cans! We used to shoot them in the garbage dumps when rat hunting, so there wasn't an environmental impact.
5. Road apples (otherwise known as horse turds): We have used these. They have the advantage of being totally biodegradable and are renewable ecologically, as long as there is a horse or ass around. Non-fresh examples are easily tossed for shotgun practice. However, sadly, they are not very reactive -- we thought they would explode, but alas, they didn't.
@moulindu
I loved your system!