Files with mc3 suffix are match-casting geometry control files from BD3 bridge modeling tools. Seems outdated.
Software that open mc3 file
MC3 file extension - Bridge Design Modeler 3D match-casting geometry control
What is mc3 file? How to open mc3 files?
File type specification:
File extension mc3 seems to be best known for its use in now discontinued software called Bridge Design Modeler 3D (BD3). A .mc3 file used in DB3 contains 3D match-casting geometry control.
The default software associated to open mc3 file:
BD3 
(obsolete software)
Company or developer:
Interactive Design Systems
BD3 is essentially a 3D version of Bridge Designer. In BD3 the members are 6 degree of freedom beams and the displacement field is 3-dimensional (3 translations and 3 rotations).
List of recommended software applications associated to the .mc3 file extension
Recommended software programs are sorted by OS platform (Windows, macOS, Linux, iOS, Android etc.)
and possible program actions that can be done with the file: like open mc3 file, edit mc3 file, convert mc3 file, view mc3 file, play mc3 file etc. (if exist software for corresponding action in File-Extensions.org's database).
Unspecified and all other actions for computer programs working with mc3 file - Bridge Design Modeler 3D match-casting geometry control
Click on the software link for more information about BD3. BD3 uses mc3 file type for its internal purposes and/or also by different way than common edit or open file actions (eg. to install/execute/support an application itself, to store application or user data, configure program etc.).
Microsoft Windows:
BD3 (obsolete/discontinued)
