Temporary Archive: Suzanne Brockmann's Message Board

Okie dokie—demo 101. Most demo is very stable—slap it stomp on it shoot it—nothing—and it is very precise in how it acts—thus the ability to use it for cutting etc. Varying speeds of explosives are very important when determining how an explosive will work. The higher the speed, the higher the “brisance” or shattering effect and the lower the speed the greater the pushing power. So, a low speed explosive like ammonium nitrate will be used to move earth—a high speed explosive like semtex will be used to fracture rock. The blasting cap is the sensitive part of the explosive train—usually made with a small amount of petn and rdx, the blasting cap can be set of electrically or non-electrically (burning fuse)or by inadvertantly shutting in a car door-- Most military demo is non-electric and set off with an instantaneous fuse called nonil using distance to keep you safe (vice time)—okay, so, usually you will set up your demo before hand—or you might have a few different charges set up. The main charges will be separated from the blasting caps—usually two people will be carrying blasting caps and no explosives. The demolition will be set, and then the “cap men” will tie the blasting caps into the explosive chain. Pull the fuse and depart the area.. Military explosive are self oxyenigated—i.e., they have enough O2 in their make up to allow them to explode without air. Blasting caps are sealed with glue after the fuse is inserted, and the fuse itself is also self-oxyenigated