In cleaning up my very cluttered office space today at the insistence of my wife, I ran across a shell I didn’t remember I had, and I don’t remember even where I got it. It is a dummy or drill round (2 holes in the brass case, no primer) that is headstamped (in part) 1"10 Mk. I 75 cal. and there is also an anchor stamp. The projectile has a brass or copper driving band and appears to be of steel and about 1" in diameter. Date is “9-42” I’d suspect it is either US Navy or Royal Navy. So what is it and what gun was it used in? Should be a few old salts out there that are familiar with this.
I think I found the answer on Wikipedia - an AA gun used by the US Navy in the early part of WWII.