An exploding target is a type of explosive that after being shot by a 223 or other larger rounds explodes upon the impact of the bullet. It is usually a mixture of aluminum powder and ammonium nitrate. Exploding targets are legal to produce but are restricted and may sometime be required to seek permission from the relevant authorities. Responsibility and safety is paramount when it comes to exploding targets. Before coming up with any recipe one should always focus on safety.
An explosive is only created when two or more parts are mixed. In an exploding target recipe, one part should be the oxidizer while the other should be the catalyst. The oxidizer supplies extra oxygen to the catalyst thus making the explosion possible and very powerful. You can use ammonium nitrate as the oxidizer and dark aluminum powder (dark aluminum flake) as the catalyst. There are other options of mixing with other components in order to change the blast characteristic. However, the earlier mentioned are the basic ones and often work well with a majority of center fire rifle rounds. 223 rounds can offer 100 % success. One needs a container for containing the mixture so as to work properly. Paper cardboard tubes or thin-walled plastic bottles work pretty well.
This is quite basic, often tried and reflects a true version. For every 0.5 pounds of oxidizer (ammonium nitrate, 1 teaspoon (5 ml) of the catalyst (e.g. dark aluminum powder) is added. The constituents are mixed until the ammonium nitrate is fully coated with aluminum. The mixture is afterwards placed into a container and then sealed. If the catalyst is not fully coated by the aluminum powder, there is high probability that it will not detonate. This recipe is simple, direct and effective.
Other recipes exist but they may be more sensitive and therefore require great caution when dealing with them. The more sensitive recipes can even be set off by static heat or shock. During the mixing of such recipes, shaking of the constituents should not be done. Instead, you should put the mix on a sheet of paper (a clean one) and while grabbing the corners of the paper, gently put it into the container. Alternatively, you can put the constituents into a big zip-lock bag to gently mix the ingredients. You should always be cautious of any static electricity. The more sensitive recipes require 5% catalyst and 95% oxidizer. They are determined by weight. These may be as follows.
The catalyst by weight is 95% dark Aluminum powder and 5% Zirconium Hydride. The oxidizer by weight is 75% Ammonium Nitrate and 25% Ammonium Perchlorate. This recipe makes the target more sensitive. The explosion is a bit louder and high pitched.
Another exploding target recipe is 97% Dark Aluminum powder and 3% Antimony Trisulphide as the catalyst. The oxidizer is 90% Ammonium Nitrate and 10% Ammonium Perchlorate. This recipe is also more sensitive and calls for extreme care. It can work with 22 rifles and shotguns.
With the right proportions of exploding targets, you can be assured of big bang. All you need to do is to place the container in an open space and then have fun. A single shot will be enough but you should be about 100-150 yards from the target.