having a pump integrated into the gun question????

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jvw1979
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Mon Oct 03, 2011 5:10 am

Hey guys here is some progress pics.

Mostly it's just a mock up for now, I tested and the hammer valve piloted piston valve works perfectly, the hammer valve does take quite a bit to actuate.. but like most problems I will just use a bigger hammer.

So far I tested it to 90psi(6bar) only. As my little compressor cant manage much more. It's leaking quite badly in places, that will be fixed with final assembly. Add more Teflon tape.. hehe

The idea is to have a quite significant secondary chamber, this will open with the breech (tap load) to to fill the main chamber, then close off the secondary storage chamber when the bullet is lined up with the barrel. I love the mechanical linkages. Should also cock the hammer at this time.. but all that will come later.

Here is some pics of what I have so far.

Ay advice on sealing all those pipe fittings aside from teflon tape?
Also how high do you think I could go in terms of pressure, All the pipe work there is cast iron fittings, galvanized welded seam pipe. and brass for the valve housing. Oh and of course the copper barrel. Engineeringtoolbox.com reckons 150psi.. That does seem a little conservative to be honest. But hey dont want my face blown off.

To the guys that responded initially, yes I deviated from my original plan compeletely... it's a 13.5 ID mm barrel now at 98 cm long.

I'm still planning on having a pump built in to the gun, but it will just pump up the primary chamber, so the idea is have the secondary chamber put in some initial air and then I will up the power of the shot with with the built in pump connected to the primary chamber, or I could just leave the big secondary chamber open and then I have semi auto. as soon as I figure some loading system with the top tap load. With a lot of effort leaving that secondary open i could then pump up that chamber too .. although that would take some effort.

P.S. Sorry for the bad full length pic... blackberries don't autofocus too good.
Attachments
Tap load breech open
Tap load breech open
Tap load breech closed
Tap load breech closed
hammer piloted piston valve
hammer piloted piston valve
mock up, still requiring a fill connection and and additional ball valve to seal off the "buttstock" secondary chamber.
mock up, still requiring a fill connection and and additional ball valve to seal off the "buttstock" secondary chamber.
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wyz2285
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Mon Oct 03, 2011 10:38 am

looks good, keep on!
I didn't see the hammer...
I don´t think you need a pump integrated, with your chamber and piston valve the pressure is enough, a integrated pump will just occupy space from the main chamber
CpTn_lAw wrote: :D "yay, me wanna make big multishot pnoob with 1000 psi foot pump compressor using diamond as main material. Do you think wet bread make good sealant? " :D
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