This is the same carbine, in a half-unfolded format, WITHOUT complete modeled parts on the interior surfaces yet ("there are blobbed-in rectangular blocks standing in place of finished parts to demonstrate functional form factor"). This is a normal part of my development process, the blobs get refined into finished parts as standard components that can have their geometry checked across multiple modeled formats (open, closed, half folded, all parts of the duty cycle of the bolt/barrel reciprocation, all parts of the trigger assembly duty cycle, etc), and part of why I like to use an old version of sketchup that lets me do this on my local machine quickly and easily.

I'm experimenting with doing a stream of all my sequences of failures making CAD models of guns that I'd like to see exist in the world someday.