You can find the full moon clips at
www.egunparts.com which is Numrich's online site. I was able to get both full and half moon clips for my S&W Model 1917.
As to history, I can't give specifics but from what I understand, the US Army didn't have enough Model 1911 .45 Autos for WWI. And it was easier to have Colt and then S&W take existing revolvers and chamber them for .45 ACP. If you saw the 'The Lost Battalion' with Rick Schroeder, he was armed with a .45 revolver.
Hope this helps.
-John
On Wed, 4 Dec 2002 01:23:23 +0000 (UTC), 'Paul Hug'
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