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A number of proposed warhead concepts require an explosive charge which is detonated at a long distance from the target to form a heavy, high velocity fragment which acts as a kinetic energy penetrator to efeat armor. Two such concepts are STAFF (Re-f-h and SADARM ( which are envisioned to attack tanks from the top, where t e armor is relatively thin. A charge design which can accomplish this task is that known as the ~self—forging fragment(SFF) ’ device or as the ~Projectile—forming charge (P_charge).~~~In ~~contrast to a conventional conical shaped charge which produces a jet having a tip velocity of up to 10 km/s and is capable of perforat— ~ ~ ing very thick armor at short standoff distance, a SFF device formsits liner into a single slug or fragment which remains in one piece as it flies over a trajectory of 100 meters or more at a velocity apprcaching 3 km/s. While the depth of penetration achievable by a LU 5FF is much less than that of a conventional jet forming shaped ~~ ~ charge operating at short standoff distance, its performance at very ~ ~ Li.... long standoff is only slightly degraded by its loss of velocity dueto air drag. SYF devices are the only chemical energy warheads C~ ~ capable of significant effect at standoff distances exceeding severaldozen c~1.ibers. Designing a SFF device is not an easy task, since the liner must be contoured so that the explosive impulse forms it into a slug which has a very low velocity gradient, otherwise it will be pulled apart. Conceptually the job is like forming a cannon ball from a sheet of material with one blow of a hammer, without a die. At ARRADCOM~s Large Caliber Weapons Systems Laboratory, the HEMPcomputer code has been developed to serve as an effective design tool to simplify this task considerably. Using this code, warhead