Old Miltary scope question

[Mesa]

I have what I think is an old military scope. It says:
TELESCOPE M33 NO 828
E.K. CO 1942 FM

It's very heavy for it's size. See the attached pictures. Anybody know what this is?

-Mesa

 

[deadin]

I don't believe that it is a rifle scope. (No adjustment knobs and no crosshairs) Probably a spoting scope of some sort or another.
The E.K. could probably stand for Eastman Kodak. They made a lot of optics for various uses.

Dean

 

[Mesa]

It has a non-removable mount. I figure the windage and elevation must be on the base it mounts to. I'm skeptical that it's a rifle scope too.

 

[ABTOMAT]

It's a scope from a 75mm canon, I think the self propelled gun version of the M3 halftrack. Goes into Mount M36 which is part of the fire control.