American Handgunner Smith & Wesson Model 1917 - American Handgunner
Perhaps the British could claim at least a small amount of credit for the advent of Smith & Wesson’s Model 1917 .45 Auto revolver. Just into World War II they first contracted with the company to buy Hand Ejector, 1st Model revolvers famously known as “triplelocks” converted to fire their .455 Webley cartridge. Besides that third lock securing the cylinder crane to the main frame, those handguns also had a shroud covering the ejector rod on three sides.
Source: americanhandgunner.com