UNCLASSIFIED erenc .50 Caliber Limited Range Projectile Informational Brief for NDIA Joint Armaments Conference Presenter: Stephen McFarlane, US ARMY ARDEC, RDAR-MEM-I Unclassified BLUF • The Small Caliber Ammo Development team was funded to investigate the feasibility of a pyrotechnically actuated disassembling Limited Range .50 Cal bullet • Conceptual designs were evaluated via modeling and simulation • Proof of concept test was performed • Results indicate the need for concept refinement and pyrotechnic mix improvement Unclassified Project Objective & Warfighter Benefits Project Objective • Exploit recent advancements in structural reactive materials to create a projectile that dissembles at a predetermined time of flight Warfighter Benefits • Reduced risk of collateral damage • Ballistic match with standard round to max effective range • Decreased (design programmed) maximum range • Caliber .50 training in range restricted areas Unclassified Briefing Overview • Solid model development • Ballistics Modeling and Simulations • Proof of concept test and test results • Phase 1 summary Unclassified Concept 1 Design goal 1st Iteration • Initiate pyrotechnic mix with propellant during launch • Pyrotechnic mix intended to ignite Structural Reactive Material (SRM) at predetermined position during flight 2nd Iteration • Reacted SRM intended to result in disassembly of projectile sections 3rd Iteration * Patent Pending Unclassified Concept 2 Design goal • Initiate pyrotechnic mix with 1st Iteration propellant during launch • Pyrotechnic mix intended to ignite Structural Reactive Material (SRM) at predetermined position during flight • Reacted SRM expected to melt 2nd Iteration copper jacket resulting in structural failure of the projectile 3rd Iteration * Patent Pending Unclassified Concept 3 Design goal • Similar to concept 1 • More robust interlocking feature * Patent Pending Unclassified M&S Results, Interior Ballistics Pressure vs. Time Concept 1 Concept 2 45000 40000 35000 si 30000 p e, 25000 ur20000 s s15000 e r P10000 5000 0 0 0.001 0.002 0.003 0.004 0.005 -5000 Time, s Concept 3 M8-API • Used theoretical M8 PT curve for 36in Barrel • Compared the plastic strain and engraving • Deformation evident • All concepts will survive gun launch and have similar plastic strain as the M8 • Theoretical muzzle velocities, assuming powder charge varied to achieve PT similar to that of M8 – Concept 1, 2910ft/s – Concept 2, 3096ft/s – Concept 3, 2620 ft/s 36in Barrel – M8, 2700 ft/s Unclassified M&S Results, Exterior Ballistics Caliber 0.50 Limited Range Estimate Trajectory Match AND Limited Range m) e ( M33 ud Separated Projectile Altit Hi-Drag Estimate Range (m) Caliber .50 Limit Range Designs Caliber .50 Limited Range Designs Mach Number versus Range Gyroscopic Stability Factor vs Range h Number CCCooonnnccceeepppttt123 S_g CCCooonnnccceeepppttt123 c a M Range (m) Range (m) Unclassified M&S Results, Terminal Ballistics M33 Cal 50 Ball • Penetration simulation of impact with 3/8” RHA at approximately 200m • Validated penetration models with historical data (Francis Mascianica) M33 M8 M33 M8 • Impact Velocity, Vs = 2500 ft/s • Impact Velocity, Vs = 2500 ft/s • Residual Velocity, Vr = 1297 ft/s • Residual Velocity, Vr = 1696 ft/s Unclassified