“DISTRIBUTION STATEMENT A: Approved for public release; distribution is unlimited” The views, opinions, and/or findings contained in this report are those of the author(s) and should not be construed as an official Department of the Army position, policy, or decision, unless so designated by other documentation. The citation in this report of the names of commercial firms or commercially available products or services does not constitute official endorsement by or approval of the U.S. Government.

May 16, 2012 Daniel L. Cler - ARDEC

Test Techniques for Next Generation Weapon Suppressor Development

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Small Arms Suppressors For Automatic Weapons

• Suppressors Used to Reduce Weapon Noise • Bolt Action/Semi-Automatic Weapon Suppressors

• Relatively simple • Can focus on maximum sound reduction

• Automatic Weapon Suppressors • Pluses

Improved command and control Reduced hearing loss Reduced signature

• Minuses Difficult to engineer More flash More heat Increased blowback, noxious gases and fouling Increased bolt velocity Reduced weapon reliability

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Good Suppressor Design For Automatic Weapons

• Systems Approach Required • Balance of sound, flash, thermal, blowback, weapon

powering, and dispersion • Good designs balance all six

• Modeling and Simulation • CFD to evaluate sound, blowback, thermal, gas temperature,

and weapon powering • More insight into critical performance features • Quick way to evaluate and improve designs

• Testing • Validates results and determines absolute performance

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Critical Test Techniques Automatic Weapon Suppressor Design

• Current Testing For Bolt Action/Semi-Automatic Weapons • Sound measurement • Dispersion measurement

• Required Measurements For Automatic Weapons • Sound measurement • Flash measurement • Thermal measurement • Weapon blowback measurement • Weapon powering measurement • Dispersion and POI shift measurement

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Test Setup – Blast, Flash, Thermal Army Research Lab (ARL) Aerodynamics Experimental Facility (AEF)

PCB106B Gage – 1 m, 10 Deg

PCB337A1 Gage – 1 m, 90 Deg

PCB337A1 Gage – 1 m, 170 Deg

Four Omega OS523E-3 IR Thermometers Suppressor and Barrel Temperature

10 Deg

Rigid Weapon Mount

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Test Setup – Blowback ARL - AEF

PCB 106B Gage Blowback Measurement

MTI Instruments Microtrak II LTC-300-200 High-speed Laser Displacement Sensor Bolt Velocity Measurement

Feed Cover Tray Strapped Up

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High-Speed Shadowgraph Standard Flash Hider

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High-Speed Flash Video Suppressor A

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High-Speed Flash Video Suppressor B

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Open Shutter Flash Single Round M80 – First Round Flash

Suppressor A Suppressor B Standard Flash Hider

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Measurement Comparison

Max Flash Max Sound at Shooter’s Ear Temp Change

Blowback at Breech Bolt Velocity Dispersion

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Conclusions • Six Critical Measurements for Automatic Weapon

Suppressors • Sound • Flash • Thermal • Blowback • Weapon powering • Dispersion and POI shift

• System Based Suppressor Design for Automatic Weapon Suppressors • Trade-off Between

Flash and sound Vs.

Thermal, blowback and weapon powering • Compromise of sound level required to get a functioning automatic weapon