Recording anechoic gunshot waveforms of several firearms at 500 kilohertz sampling rate

Abstract

Acoustic gunshot signals consist of a high amplitude and short duration impulsive sound known as the muzzle blast and the shock wave. This experiment involved documenting gunshot muzzle blast sounds produced by eight commonly used firearms including Remington 870, Colt 45, Glock 19 with 9mm ammunition, Glock 23, Sig 239, AR15, 22LR, and Ruger SP 101 with 357 magnum and 38 special ammunition. An elevated microphone bracket (3m above the ground) was built to achieve a quasianechoic environment for the duration of the muzzle blast. Twelve microphones (GRAS 40DP) were mounted on the bracket in a semi-circular arc to observe the azimuthal variation of the muzzle blast. Signals were recorded using LabVIEW. Similarities and differences among waveforms are presented.