Aeration of Explosives

Clapham (quoted in Ref 1, p 160), prepd simple gelatins by mixing NC with NG and allowing to gelatinize at 50° without 

Taylor (Ref 1, p 161), investigated the effect of aeration on the development of high detonation velocity in BG within 4 inches of the origin of initiation, using fulminate-chlorate detonators. He found that there was a critical density (ca 1,46 g/cc) above which high deton vel did not occur. 

The density effect was one of aeration and only creamy mixes, with very fine air pockets, were effective in promoting high vels. As the fine air-bubbles coalesced on storage and the structure became coarser, the gelatins became increasingly insensitive 

Summarizing the experience with BG, Taylor (Ref 1, p 163) stated that a non-aerated expl tended to fail in propagation of deton when initiated by weak detonators well-aerated creamy mixes with extremely fine bubbles tended to detonate at, or pick up to high vel, and gelatins of intermediate aeration tended to exhibit the low-vel regime. 

It would appear that propagating low-vel is not achieved in small diam cartridges with non-aerated BG but that high-vel propagation can be obtd with such material if a moderately powerful initiator is used 

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