So if the spent shells aren't flying out then what's the point? I've seen people running around with the ejecting ones and they put one of those brass catchers on the side - kind of defeats the purpose surely.
Or do you mean the reloading would be more fun? That's a pretty specific niche to design a whole shell rotation system around lol. How would you get the shells out? The stock would presumably only store a handful even on the beefiest shotty.
Well, I imagined it on a UTS-15 a few months ago. I actually considered seeing if any gunsmiths would consider it, for a truely unique airsoft gun, but I also considered how difficult it might be to import a shotgun which had been modified (or was unmodified pending mods) for non lethal airsoft loads. I have not looked to see if any features on that gun prohibit import to the UK.
The system would load as normal, honestly converting a real one could work since it's pump action. Spent shells would continue past the ejection port and "somehow", progressively stack up in the stock (like how a real P90 magazine works), The best idea I had when I last considered this on this gun, was to have a rectangular box in the bottom of the stock (doublestack), which the gun's pump action would push spent shells down into, and every, lets stay it could hold 7-14 shells, when it's full the gun will not pump, and you simply press a button pop it into your dump pouch and load another.
Actually I think the most fun part (as an observer) of the shell ejection guns in the "gas-in-shell" part. And the option of alternative loads, such as a single .45g in a tube, vs 12+ .20s. or Larger BBs (diameter/circumference, not weight).
For reasons not yet clear to me, it's s.5, barrel length I think. But once modified to fire airsoft CAM Shells, it could go back down to it's usual length. Main problem is the fact that it's a real shotgun even if you had changed the size of the firing pin. Unlike the APS CAM, it has would, being real, tolerate real combustion shells. Whereas the APS CAM, as i understand it would explode with real loads.
Obviously there are lots of other issues with converting it, especially if the bore is different between the magazines. I suppose for the most part any mod would be disassemble and build replacements, rather than changing actual parts.