double flange formed at one end which is axially positioned on the crush cup 38 in operation a conventional fuze of the impact variety would detonate when hitting or striking an obstacle during its trajectory obstacles such as leaves foliage or rain would generate sufficient force to rupture the closing disc 34 collapse the crush cup 38 and force the bottom portion of the detonator pin 40 through bore 22 into bore 20 thereby initiating the round this type of conventional round cannot penetrate a canopy of foliage pass through a rainstorm or overcome the resistance of high winds and reach its intended target without premature detonation in addition greater efficiency and capability are required since fuzes are made more sensitive and projectiles and missiles are urged to high velocities to accomplish this goal it was required that a higher order was needed to solve this problem it has now been discovered that in order to secure the most effective results from such projectiles and missiles especially when they are used in tropics and directed toward densely wooded areas or during a rainstorm is to effectively completely cover the detonator accordingly the embodiment of the helical baffle was conceived as previously described herein which improves the penetrability of the shell and at the same time retains its sensitivity to impact with large objects this is accomplished with a geometry characterized by the twisted cross walls where.