Title: Development of a Sabot for Ballistics Testing

Authors: Eric J. Ancira, Farid A. Solis, Larry D. Peel, Guodong Guo, Shah Alam

DOI: 10.33599/nasampe/s.22.0805

Abstract: A sabot allows a smaller caliber projectile to be fired from a larger caliber barrel. Researchers at Texas A&M University Kingsville are developing a low-cost ballistic testing system of a vacuum cannon assisted by compressed air. A larger-diameter barrel was needed to obtain sufficiently high projectile velocities, but a smaller diameter projectile was desired, thus a sabot was suggested to carry the projectile. A steel penetrator was developed that is five times longer and has more mass than a typical bullet, requiring a lower velocity to achieve the same impact energy. Currently, a sabot and projectile are accelerated down a vacuumed barrel, the sabot is caught, while the projectile flies a short distance and impacts a composite test panel. The ideal sabot fills the larger diameter barrel, is lightweight to reduce energy usage, has low friction with barrel walls and the penetrator, and ideally, would withstand repeated impacts without failure. A cylinder with a blunt conical nose and a central projectile holder was determined to be fairly optimum and stable after several iterations of simulation, fabrication, and testing. Other performance factors include dynamic stability, low sliding friction, and ease of fabrication. Sabots were cast using Shore A90 polyurethane with chopped fiberglass and were also 3D printed from nylon, TPU, PLA, and glass-reinforced nylon, and evaluated. All function for one shot, with the TPU, nylon and cast PU/fiberglass sabots having the best durability and ease of use. The researchers currently have a variety of stable, lightweight, low friction reusable, and non-reusable sabots to use.

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Conference: SAMPE 2022

Publication Date: 2022/05/23

SKU: TP22-0000000805

Pages: 19

Price: $38.00