A new, practical distributed charge, called the "Broomstick" Distributed Charge, has been developed. The underlying principle is one of the first to be applied to distributed charges, and has been used for many years in experimental work. It comprises an explosive charge in the form of a length of Primacord wound in a helix around a long slender mandrel. In the Broomstick Charge the mandrel is a wooden rod 5 ft long and approximately 1 1/2 in. in diameter with helical groove throughout its length in which the Primacord is wound. The pitch of the helix is chosen to produce the required detonation velocity along the axis of the rod. The rods are joined by threaded couplings that permit the Primacord detonation to pass from one rod to the next. A 50-ft long Broomstick Distributed Charge can be made with a total explosive weight as small as 1 1/2 lb, which is of distinct advantage for obtaining high-resolution in many areas. If larger charge weights are desired, concentrated charges (canned explosive primers) can be coupled between adjacent rods. The charges can be assembled rapidly, are rugged enough to withstand poling into the hole, and leave a fairly clean hole when detonated.

This content is PDF only. Please click on the PDF icon to access.

First Page Preview

First page PDF preview
You do not currently have access to this article.