Lead block expansion test tetryl

According to Medard [12], in the lead block test nitromethane gives figures similar to picric acid. T. Urbanski and Pawelec [35] found 325-360 cm3, averaging 345 cm3, i.e. 110% of that of picric acid. The same authors determined the lead block expansion when nitromethane was detonated by means of a No. 8 detonator Mid 1 or 5 g of tetiyl. The expansion given by tetryl was deducted from the bulk expansion (Table 126). 

In the small Trauzl test pentryl caused an expansion of 15.8 cc., while the same weight of tetryl caused one of 13.8 cc., TNT 12.2 cc., and picric acid 12.4 cc. In the small lead block compression test, in which 60 grams of the explosive was exploded by means of a detonator on top of a lead cylinder 64 mm. long, it was found that pentryl produced a shortening of the block of 18.5 mm., tetryl 16.6 mm., picric acid 16.4 mm., TNT 14.8 mm., and diazodinitrophenol 10.5 mm. Determinations of velocity of detonation made with half-meter lengths, the explosives being... 

As for its explosive strength, guanidine perchlorate is similar to tetryl. Its sensitiveness to shock is comparable with that of picric acid. The rate of detonation is 6000 m/sec at a density of 1.15 and the net expansion in the lead block test is about 400 cm3. 

TNA shows about the same sensitivity as tetryl in the drop test. Lead block experiments have been reported which showed that 10 grams of TNA produced a net expansion of 430 cc., TNT 254 cc., picric acid 297 cc., tetryl 375 cc., guncotton 290 cc., and 75 per cent dynamite 300 cc.76 Experiments with the manometric bomb gave the results indicated below. 

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