Final report. Generai Thomas J. Rodman laboratory Rock Island arsenal, Rock Island, Illinois, 1977, -189 p.An analysis was conducted on the performance of M16A1 rifles made by three manufacturers with the use of two kinds of ammunition and three rates of fire. A data include extreme spread and here erosion gage measurements, each as a function of the number of rounds fired. Consistency is lacking in the experimental data, even though identical tests were performed. Probably, a random vibrations of the gun barrel or other unknown phenomena may be the reason for Inconsistency of spread data. The inconsistency In the penetration of erosions gages may be due to fouling deposits on the bore surface and to lack of properly designed tools for unique measurements. Large variations, occur In the useful life of the barrels due to variations in manufacturing, ammunition, and firing rate. The typical rate of erosion is about one-thousandth of an inch per thousand rounds of fire. Gage Number 6 may be used to measure barrel erosion and ultimately to Indicate when to discard the barrel. The erosion increases and the useful life of the weapon decreases with increase in rate of fire. The useful life of the weapon may be approximated as Inversely proportional to the two-third power of the firing rate.Contents:
Introduction.
Identical Tests.
Gage penetration.
Bore Profiles.
Gage analysis.
Recommendations.
