I have a .pdf version of the US War Department Technical Manual 9-285 Shotguns, All Types September 21, 1942.

I'm happy to e-mail it to anyone who wants it, just send your e-mail address to me at sleepla8er@hot-shot.com

This TM was found online, but I don't remember where and the maximum upload file size on the forum does not permit me to post it here.