Anyone know what this is? Help identifying

[ogfarmer]

it is definitely a mystery gun. If only it could talk. I appreciate all the ideas everyone has thrown out there, it does look alot like all of the suggestions,

 

[JRH6856]

there was a .45 issued to U.S Army generals called the M15. It had features specific to it and there were just over a thousand made. It was made by Rock Island Arsenal and in a Commander configuration.

But this was not a WWII era firearm. It was adopted in 1972 and in production until 1984 (1004 made).

 

[sixshooter357]

for me...

It looks like a Heinzelmann Pistol, Patent Heim.
If so it was made in the 30,s in Plochingen / Neckar in Germany.
Plochingen is a small Town 15 mls south of Stuttgart and is not known for a gun industrie, Heinzelmann probably run a small shop that mainly made parts for better known companies in Germany.

 

[JRH6856]

It looks like a Heinzelmann Pistol, Patent Heim.
If so it was made in the 30,s in Plochingen / Neckar in Germany.
Plochingen is a small Town 15 mls south of Stuttgart and is not known for a gun industrie, Heinzelmann probably run a small shop that mainly made parts for better known companies in Germany.

This is what Numrich lists as grips for the Heinzelmann .25

They look very different from the OP pics. Especially the screw hols number and position.

 

[Ron James]

But, even if it was a Heinzelmann ,it would be so marked on the slide according to two different references. Can't find a picture.