Axt
December 1st, 2003, 10:48 AM
Heres a few methods ive used, or at least determined to be usable for determining the properties and performance of homemade explosives. All are easy to make using no hard to get parts.
<font size="3"><b>Drop Test</b></font>
<img src="http://ww1.altlist.com/~52497/rogue.altlist.com/images/Droptest.jpg" align="right">This rig I posted before, measures the impact sensitivity of explosives by letting a standard weight fall from varying distances until detonation occurs. Constructed by using a cylindrical "hammer" that slides down a pipe. This is still best as a relative measurement, as the distance will vary between rigs using differing hammer surface areas, friction down the pipe and construction materials, therefore test the explosive and compare results on a standard explosive tested on the same rig, construction is best viewed in the movie.<a href="http://geocities.com/roguemovie3/">Movie Available</a>.
<font size="3"><b>Witness Plate Test</b></font>
<img src="http://ww1.altlist.com/~52497/rogue.altlist.com/images/leadplate.jpg" align="right">Done by detonating the explosive in the vacinity of a metal plate, ideally to crater the plate rather then denting or blowing a hole through it. For this a lead block placed on a soild steel surface is the best, the picture shows the effect of three ANNM charges (NM soaked prills) contained in 20mm PVC detonated with varying detonator placement up the charge, the results show that the 20mm column was below the critical diametre of the explosive. This isnt to be confused with the "lead block test" that uses a known weight of explosive detonated inside a hole drilled into the block.<a href="http://geocities.com/roguemovie3/">Movie Available</a>.
<font size="3"><b>Effective Peak Pressure Test</b></font>
<img src="http://ww1.altlist.com/~52497/rogue.altlist.com/images/pressurerig.jpg" align="right">By detonating the explosive underwater inside a steel vessel, water is injected into a pipe, pushing the water column up which compresses the air. This pressure rise is gauged by a simple tyre pressure gauge at the top as these are readily available and hold the peak pressure measurement. Again, this figure is only relative for comparison with other exposive tested in the same rig. The one in the picture was constructed out of 1/4" steel, though the flat base has been bent out a bit by 3 gram charges of PETN. So the base, which will be a lot weaker then the curved sides should be made a lot thicker, at least 1/2" with the 3g charges.<a href="http://geocities.com/roguemovie3/">Movie Available</a>.
<font size="3"><b>Casing Fragmentation Test</b></font>
<img src="http://ww1.altlist.com/~52497/rogue.altlist.com/images/fragments.jpg" align="right">By determining the size of the fragments of casing recovered after a detonation its possible to determine the shattering power of the explosive, use a suitable casing such as the brass cartridge case as shown in the picture, the charge is placed in a solid vessel containing water or sand and detonated, the fragments are recovered by pouring the mix through a sieve.
All give relative figures, so testing one explosive alone using any individual method will be meaningless, at least two explosives must be used to get a relative figure. Post your testing methods and/or results!
<font size="3"><b>Drop Test</b></font>
<img src="http://ww1.altlist.com/~52497/rogue.altlist.com/images/Droptest.jpg" align="right">This rig I posted before, measures the impact sensitivity of explosives by letting a standard weight fall from varying distances until detonation occurs. Constructed by using a cylindrical "hammer" that slides down a pipe. This is still best as a relative measurement, as the distance will vary between rigs using differing hammer surface areas, friction down the pipe and construction materials, therefore test the explosive and compare results on a standard explosive tested on the same rig, construction is best viewed in the movie.<a href="http://geocities.com/roguemovie3/">Movie Available</a>.
<font size="3"><b>Witness Plate Test</b></font>
<img src="http://ww1.altlist.com/~52497/rogue.altlist.com/images/leadplate.jpg" align="right">Done by detonating the explosive in the vacinity of a metal plate, ideally to crater the plate rather then denting or blowing a hole through it. For this a lead block placed on a soild steel surface is the best, the picture shows the effect of three ANNM charges (NM soaked prills) contained in 20mm PVC detonated with varying detonator placement up the charge, the results show that the 20mm column was below the critical diametre of the explosive. This isnt to be confused with the "lead block test" that uses a known weight of explosive detonated inside a hole drilled into the block.<a href="http://geocities.com/roguemovie3/">Movie Available</a>.
<font size="3"><b>Effective Peak Pressure Test</b></font>
<img src="http://ww1.altlist.com/~52497/rogue.altlist.com/images/pressurerig.jpg" align="right">By detonating the explosive underwater inside a steel vessel, water is injected into a pipe, pushing the water column up which compresses the air. This pressure rise is gauged by a simple tyre pressure gauge at the top as these are readily available and hold the peak pressure measurement. Again, this figure is only relative for comparison with other exposive tested in the same rig. The one in the picture was constructed out of 1/4" steel, though the flat base has been bent out a bit by 3 gram charges of PETN. So the base, which will be a lot weaker then the curved sides should be made a lot thicker, at least 1/2" with the 3g charges.<a href="http://geocities.com/roguemovie3/">Movie Available</a>.
<font size="3"><b>Casing Fragmentation Test</b></font>
<img src="http://ww1.altlist.com/~52497/rogue.altlist.com/images/fragments.jpg" align="right">By determining the size of the fragments of casing recovered after a detonation its possible to determine the shattering power of the explosive, use a suitable casing such as the brass cartridge case as shown in the picture, the charge is placed in a solid vessel containing water or sand and detonated, the fragments are recovered by pouring the mix through a sieve.
All give relative figures, so testing one explosive alone using any individual method will be meaningless, at least two explosives must be used to get a relative figure. Post your testing methods and/or results!