Getting right down to it, I'm currently modeling out an Anti-Tank Rifle (mostly as a portfolio piece, but if it turns out well, maybe I could sell it on Cubebrush or something).
At first, I tried taking a bunch of different reference images at 20% Opacity, and overlaying them to generate a sort of "master shape" to work from.
As you can see, this did not work. (However, this method does give decent results with simpler items, such as swords and hammers)
So I went with Plan B: Pick a cool-looking reference of an Anti-Tank Rifle that already exists (A Steyr HS .50, in this case)
Sketching over the reference gave me a chance to break down the gun into separate parts, and should hopefully make modeling a lot easier.
Other than that, it's just been working in Maya to block out the basic forms.
At this point, I'm not too concerned about details, topology, or polycounts, but I'm still doing what I can to keep things clean as far as quads and edge-flow. Ideally, I'm planning on building a clean mesh that can be exported to ZBrush for finer details and normal projecting, followed by a topology cleaning pass back in Maya, before sending it off into Substance Painter for Texturing.
That's about as far as I've gotten at the moment (maybe about 4-5 hours in at this point, from the moment I started gathering Reference Imagery).
Comments/Suggestions/Critiques/Feedback are always appreciated,