We are well aware of projection-type gun games. The vast majority are electromechanical and do not use CPUs or ROMs, so there's nothing to dump, just filmstrips and artwork to scan and preserve (which is still a worthy project, to be sure). In fact, most barely use "discrete logic" - they use very simple electronic/optic relays and timers to determine whether shots hit or missed, and the analog electromechanical film projector. As such they are not very good targets for MAME to emulate in the future.
However, given that MAMEWorld.info forums has as a member the world's largest Wild Gunman fan, I've been thinking of adding it to the Undumped wiki for nostalgia purposes, and writing a little about the problem.

We're well ahead of you on this particular topic by over a decade, check out my involvement in this trip down memory lane:
http://www.mameworld.info/ubbthreads/showthreaded.php?Cat=&Board=mamechat&Number=301698#Post301698and here:
http://www.mameworld.info/ubbthreads/showthreaded.php?Cat=&Board=mamechat&Number=246012According to gregf I "named that game" in spring 2002. Time flies!
Since that time, greg has acquired manuals and schematics to various projection games and others, and I would argue that he's one of the emulation community's "experts" regarding projection games and their emulation feasibility. He goes a little into the problem here:
http://www.mameworld.info/ubbthreads/showthreaded.php?Cat=&Board=mamechat&Number=256881Reminder: The main purpose of the Undumped wiki is to list (with citations) all games that are not dumped. We are probably going to move into adding more discrete logic games with nothing to dump as a side project:
http://www.emulab.it/forum/index.php?topic=3943.0but even these have complex schematics and circuitboards that can be simulated at a low level, and many generate a video signal for display and audio as well.
Wild Gunman and most other projector games really do not do much of the sort, from what I understand. We're really uncertain whether we can adequately and reliably simulate these in MAME, but I think they will more likely be destined for some spinoff project.
The Laser Clay Shooting System you mentioned earlier may be an exception, though we won't know for certain until we see full manuals and schematics and/or PCBs.
http://www.emulab.it/forum/index.php?topic=3955.0