This is an animation showcasing all of the internals working when operating and shooting this mything firearm, along with a demonstration of the rig systems sued for the animation process.
Now that brought back memories! I used to own one of these back in the late 1970s, early 1980s. It caused no end of trouble when it was stolen, the Police were not pleased to know that such an item was on the loose. I never could shoot straight with it, so I used to shoot other people’s rifles at the shooting club and in return let them shoot the C96. As it was such a classic collectors piece I got to shoot a lot of rifles.
My take on what you have done:
The mechanics would be a lot clearer if you kept the camera static as the mechanism operates and progressed through the animation more slowly. I know that raises render times but you have done such a superb job of the model that it will be worth it. Zooming in too much makes it less clear what is going on, having a static view of the whole mechanism as it works would improve the clarity a lot.
The model is excellent and the cutaway technique you have used is superb.
As for the render times, the video was rendered with Eevee, so it’s really not a big deal, it’s maybe just because that’s the kind of pacing I’m used to, I guess
Making a more static version of the video would not take me much time, maybe it could be worth making another version
The cutaway view was created in shader, using a linear gradient mapped to an empty in the scene, which is then plugged to the shader’s Alpha channel. Lastly, backfaces are replaced with a red solid colour.
The node setup for the transparency looks like this: