Muzzle Blast Measurements on Howitzer, 105mm, M2A2E2 with Muzzle Brake No. 8
ARMY MATERIEL COMMAND ABERDEEN PROVING GROUND MD HUMAN ENGINEERING LAB
Pagination or Media Count:
Measurements of muzzle blast in the crew area of the 105mm Howitzer, M2A2E2, with Muzzle Brake No. 8, were made primarily to determine the peak overpressures produced. Measures of positive impulse and duration of positive phase were also made. The howitzer was fired at elevations of 1 degree - 14 minutes, 35 degrees - 0 minutes, and 70 degrees - 0 minutes with 2 propelling charges Charge Zone No. 10 7.22 ounces of T34 and 3.75 pounds of M17 and 115 per cent of maximum rated pressure 7.22 ounces of T34 and 4.00 pounds of M17. Some of the overpressures measured were high enough to rupture unprotected human eardrums. It is recommended that attempts be made to lower the peak overpressure below 4 psi. If this criterion is not met, ear protection should be mandatory.