Good Catch on that insider picture! I was looking at that same picture and I think you all may be right about the gaps. The toy rifle that comes with the 12" doll and the action figure sort of has the gaps too- except that the plastic kind of fills in between the barrel and the cleaning rod.
The good thing is that I can always take my clear resin parts out and not effect the rest of the gun! The are held in place by a tiny bit of glue and the silver rings
But they look really cool- so maybe I'll leave them until they break or get really scratched up.
I scratchbuilt my scope mounts out of some PVC pipe and styrene. I used bondo to fill in the middle and make the perfect contour to mount over the barrel. However, since I needed 2, I molded the original and made resin ones for the finished rifle, so sure, if anyone wants them, I can make some more.
I'll try to post a better picture of it later tonight or tomorrow.
I am pretty much out of the casting metal, but if I can get some more, I still have the mold for that too. It would require some serious sanding to get the nice shiny finish though
-cris