Shaped Charge Jet Initiation Tests with Covered High Explosive Charges with Air Gaps

Abstract

Tests have been carried out with 5 mm thick plastic discs introduced in a 10 mm large air gap in split high explosive charges. If the second charge has a 5 mm air gap behind the 5 mm polyethylene disc a relatively prompt initiation is given. If the air gap behind the 5 mm plastic disc is only 2.5 mm an initiation occurs only in the forward direction which starts with a large build-up distance and a long starting delay time without any retonation. Finally with direct contact of the 5 mm thick plastic disc to the second charge no detonation starts in the given geometry. These tests do not confirm the initiation theory to avoid impacts of powdered high explosive charge particles which can cause the initiation of the second charge. The reason could be the earlier discussed desensitization by the precompression of the bulging cover material into the high explosive charge.