Ned Simmons wrote:

SNIP

One of the most widely used alloys for underwater marine
hardware is 85-5-5-5 (Copper-Tin-Lead-Zinc), usually
pronounced 85-three-5. The ASM Metals Handbook refers to
85-5-5-5 as a bronze. SNIP

I've also seen the same alloy called "Gunmetal" (from British catalogs)

supposed to be easy machining (often appears in steam engine kits)

JK