Performance of 20mm and 7.62 mm Ablative Ammunition.
Abstract
M55 A2, 20mm ammunition modified with gelled dimethyl silicone to reduce barrel heating and erosion was found to cause heavy coppering in unplated M61 barrels. Extensive single-shot and burst screening tests of decoppering and lubricant additions to the silicone were fired. The one candidate silicone-modified (ablative) ammunition showing good promise in unplated barrels was that having projectiles with sintered-iron rotating bands. Limited testing in chrome-plated M61 (Vulcan) barrels indicated that the performance of the silicone- modified ammunition in chrome-plated barrels was highly promising. Coppering deposits were nearly stable in thickness after the first 175-round burst, and no measurable erosion took place in the test barrel and in the 973 rounds fired. Silicone-modified 7.62mm ammunition was also studied. Erosion tests in unplated M60 machine-gun barrels indicated a yaw life of 7595 rounds versus 4419 rounds with standard ammunition. Limited firing of 2800 rounds of silicone-modified ammunition in lined and plated M60 barrels indicated that much greater life improvement than the above-mentioned would be expected in chrome-plated barrels. Barrel heating reductions due to the effect of the silicone ablator were measured. Tests were carried out of the cook-off performance of ablative ammunition in M60 barrels modified to simulate the Minigun. An increase of at least two:one in the single burst length safe against cook-off was estimated for the Minigun. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1972
- Accession Number
- AD0907041
Entities
People
- D. J. Sudlik
- F. A. Vassallo
- W. J. Baran
- W. R. Brown
Organizations
- Calspan