Results of Chambrage Experiments on Guns With Effectively Infinite Length Chambers

Abstract

In previous work the effect of chambrage, the ratio c-' the diameter of the propellant chamber to the barrel bore of a gun, hai been analyzed theoretically. This analysis has been applied to a gin of effectively infinite chamber length and of varying chamber diameters in which the propellant is all burned before the projectile begins to move. The present paper describes experiments perfo.xn-ed to check the theoretical results. These were conducted with two different length 0.50 caliber gun barrels and with chambers of various diameters up to 2.44 inches. Air was compressed in the chamber behind light plastic projectiles, which were released at the proper pressures. T'e projectiles broke timing wires outside of the gun barrel, yielding projectile velocities. The experim3ntal and theoretical results are in very good agreement.

Velocity Control of Diaphragmless Vertical Gas Gun for Low Pressure Ranges

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