Accession Number : ADA313441

Title :   Evaluation of Lubricating Composites for the M16A1 Rifle.

Descriptive Note : Technical rept. Jul 74-Jun 75,

Corporate Author : ROCK ISLAND ARSENAL IL

Personal Author(s) : Murphy, George P., Jr. ; Bornong, Bernard J.

PDF Url : ADA313441

Report Date : FEB 1976

Pagination or Media Count : 41

Abstract : A previous firing test made on one M16A1 rifle indicated that a combination of self-lubricating composites applied to the bolt carrier group and a solid-film lubricant coating applied to the upper receiver tracks could reduce malfunctions and maintenance time as compared with conventional lubrication. A follow-up test was carried out with five composite-lubricated rifles and one MIL-L46000A lubricated rifle as a control. The composite inserts, though slightly different in shape, were placed in the same areas as for the original test. The test on the five composite-lubricated rifles had an average of six malfunctions to with one in the original test. Three of the rifles were terminated before 10,000 rounds because of the fracture of the inserts. In one of these rifles the bolt e sealing ring insert broke; this action caused the sealing ring to break. In the other two composite-lubricated rifles removed from test, the inserts in the cam path area fractured and fell out because, when the insert hole was machined, it broke through the cam path wall. The impact of the cam pin against the exposed portion of the insert eventually caused cracking. Nevertheless, there tests have demonstrated the feasibility of the use of the self-lubricating inserts. However, care must be exercised to insure that the inserts fit properly and are backed up with sufficient high-strength material.

Descriptors :   *COMPOSITE MATERIALS, *RIFLES, *LUBRICATION, TEST AND EVALUATION, MAINTENANCE, FIRING TESTS(ORDNANCE), CRACKS, PATHS, FRACTURE(MECHANICS), HIGH STRENGTH, WALLS, CAMS, RINGS, MALFUNCTIONS, PINS, SEALS(STOPPERS), BOLTS, INSERTS, SELF LUBRICATION.

Subject Categories : Laminates and Composite Materials
      Guns

Distribution Statement : APPROVED FOR PUBLIC RELEASE