I have an empty brass shell that I need some help identifying; can anybody tell me what this is (caliber, nationality, history)? Diameter is ~1 1/16" at the base of the rim and ~5/8" at the mouth. Thanks in advance.
I don't know about the headstamp but from the dimensions it looks like a 14.5×114mm Russian case. Started out in PTRS and PTRD anti-tank rifles during WWII. Later used in other heavy machine guns including ZPU anti-aircraft guns and on BTR APCs.