Get the Lead Out
NAVAL SURFACE WARFARE CENTER INDIAN HEAD DIV MD INDIAN HEAD United States
Pagination or Media Count:
In the interests of environment responsibility, the Navy is seeking replacement for lead decoppering agents. These agents are necessary to remove the copper deposited on the barrel surface of a gun firing copper-banded projectiles. A brief review of the theory of decoppering will be presented to provide the rationale for our choice of bismuth as the replacement for lead. Our tests program was being conducted in the 554 gun because the problem of lead toxicity poses two problems in this system not only the environmental discharge during firings, but the propellant, Naco, contains a lead salt, rather than using lead foil. Protection of the workers manufacturing Naco from the lead salt incurs significant additional expense. Naco was made without lead, fired in a pair of barrels in an attempt to copper the barrels. Though 156 rounds were fired from the each barrel, neither showed any measurable coppering. One barrel did show moderate amounts of copper in bore-search examination. After a single round of either a charge loaded with 5g of bismuthtin foil or the standard Naco, the barrels were completely cleaned of copper.
- Metallurgy and Metallography