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 5mm air gap behind the 5mm polyethylene disc a relatively prompt initiation is given. If the air gap behind the 5mm plastic disc is only 2.5mm 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.