thanks!
the black strips are temporary - grip tape like for hockey sticks. comes off easy. that is there only to hold the pieces together for initial fitting. btw, it is
very comfortable to hold - the way the bottle hangs off the bar, along with the back end of the bar, makes for a great shoulder stock.
for the final build, all the parts will be bolted together, mainly to the aluminum bar. since that's the pressure chamber, all penetrations will have to be sealed.
hose clamps or other ghetto straps won't even be necessary. (although they will be on the Fernco barrel coupler to hold it on one end and adjust the friction/seal for the sliding end.
the barrel will pass thru two plastic electric conduit hangars i picked up from Lowes. better pics of them in
this thread. they're the grey pieces that the barrel passes thru (and also clamp onto the chamber on that prototype).
friction of the barrel sliding through them can be controlled by how tight you do the mounting screws. plus, it's plastic and i can sand the inside if i need/want (they're saw-toothed on the inside circumference, and the points of the teeth contact the barrel, so would be easy to uniformly sand little bit off the tips).
for the pressure chamber/body, the aluminum is not too thick (~0.125 in), but will definitely hold screws. i'll tap the threads & seal them with loctite and maybe silicone too. or, i could use thin hard rubber washers, but i think i'll get good seals with sealants.
the ends i'll seal off with thicker plate set inside, held by setscrews from outside, and silicone or other (better?) sealant. could even use epoxy, but i'd like to be able to take it apart. also have easy reinforcement method planned if one plate doesn't work.
setting the plates inside allows me to inset a little but more to protect the overpressure blowoff valve (they're touchy crawling thru the brush
), which i'll drill & tap one of the endplates for. threaded hole for the chamber pressure gage can be drilled & tapped anywhere on the body, or on the other endplate, similarly inset for protection.
however, i'm going to keep the front end clean, in fact i'll probably inset the seal plate, fill the end with epoxy, then contour it with a grinder.
btw, i'll use an 80 psi safety blowoff.
for the valve, i'll drill & tap 3/4" NPT threads right into the top of the alum chamber. might even trim off the ends of the close-nipple hanging down into the chamber to minimize entrance loss
(i'll check the books to see even how much it would buy me before i bother).
and yup, that's a gripframe off an autococker. i'd like a single-trigger, tho (not a fan of double triggers). looking for a stock Automag gripframe...
one awesome thing about this is that all the metal is aluminum - looks like i'll get to learn how to annodize!
probably end up just painting it, tho.
as i found with the blooper, the trigger will be the trickiest/hardest part, but i have idea there...
(published Cv 10.5 !!!!!)
. i'll go back to get more different pieces to protect the critical portions (trigger linkage, mainly), and maybe even a shroud for over the ASCO, as well as something for a sight rail.
