seaweed,
Thats what I've been wanting for years!!!!
1. Never made sense to me to try to hold a 5-6ft long pistol steady in the water with one hand to hit a fish.
I even went so far as to talk to Ray Odor about their old/old guns with stalks years ago.
2. Short gun shafts have many advantages. That is why I use a shaft 2-3 sizes to short for the last 10 yr. My shafts are just long enough to allow the flopper to clear the muzzle and our new slip tube shafts can be shorter yet, maybe even ending back down the track slot like in the picture of your crossbow pistol.
3. Wood doweling for the barrel of similar diameter to the RA with an enclosed track could have a SG[specific gravity] of less than the current RA, =float better than the current RA. Different woods have different SG. If other woods are used, the new epoxy gun finishes being used by many builders now would prevent delamination problems.
4. Matt888 and Griswold use a CF tube with an enclosed track on their hybred guns now and another famous gun maker is experimenting with an enclosed track AL barrel. Matt888 and Griswold both have working muzzle designs on round/dowel barrels now, as does RA of course. These new round CF and AL barrels have high floatation material inside the barrels so that water intrusion is not an issue as it is in other hollow barrel guns.
5. I think I know of a manufacture of TI rods/tubing for the sliding wire stalk.
6. Mori manufacutres a low profile trigger mechanizem for his 'reef' model guns and the RA assembly is very light weight[and cheap] and would have one of the lowest profiles in an enclosed track gun. The Riffe Euro/Euro X trigger assembly is low profile and has a side release [monster slayer:)]
7. If you are going to design a gun for reel use, I might suggest a side line release instead of a bottom line release.
8. Sooo,= take a 1 1/2in teak laminated dowel, use a ball cutter for the enclosed track, route out a corrisponding trigger pocket for a Riffe Euro or RA trigger assembly, shape the muzzle band slot, make a grip to match and attach a sliding Ti wire stalk.[ Oh, and paint it black epoxy if you wanted [seaweed :)]. Then it might even look like a pneumatic with bands [greekdiver:)]]
Tin Man may have some good ideas and he can manufacture/produce anything.
Thanks for starting this thread seaweed. I hope I can provide positive input.