Experiments on the directivity of sound emission from firearms

• Published in: The Journal of the Acoustical Society of America 2010-03, Vol.127 (3_Supplement), p.1879-1879
• Main Authors: Huseby, Morten, Fykse, Haakon
• Format: Article
• Language: English
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.3384575

Personnel firing weapons will be exposed to noise created by the expanding gunpowder gas escaping from the muzzle. The noise from a rifle is directive, up to 20 dB louder in the shooting direction than behind the weapon. Usually personnel firing a weapon is taking advantage of the lower noise level behind the weapon. However, today firearms will be used by soldiers in complex scenarios where the head of one soldier might be directly to the side or even slightly in front of the muzzle of another soldier’s weapon. Most countries training regulations have not been updated to include all effects of the directivity of firearms in complex scenarios. Unexpected results were obtained from previous measurements on weapons with flash suppressors attached to the end of the barrel. The noise may be considerably larger in front of the weapon with flash suppressor fitted. The angular resolution of previous experimental data was not high enough to provide an explanation. This motivated us to design an experimental setup where the pressure wave from the weapon is measured, at 80 cm from the muzzle, in 180 directions relative to the firing direction. The measurements are done with and without a flash suppressor mounted.