PAPH?

[DX]

I have my own checking account now, so the world of McMaster-Carr is open for exploration. One thing I've wanted to do for a while is build an APH with a piston pc. That would allow the pc to be inline with potentially CPS-like streams.

The design I have in mind might need two pumps; one to put water into the pc and push the piston back, a second to put additional pressure in the air side. A more ambitious goal would be to double stroke a single pump, pumping water with one stroke and air with the other.

Do you think this could work and provide decent power?

[Silence]

Shoot, you're going to beat me to it.

A two-stroke pump probably isn't the best idea. What if you wanted to use the weapon "water-cannon style": filling the front with water first, then pressurizing with air? What if you wanted to pressurize the rear chamber with air first and then pump normally, like a PreCharger?

The easiest thing to do would be to use a Schrader valve to pump the air - I believe joannaardway used a Presta valve in her copper SPCgH. You'd probably want a ball valve to quickly discharge the air though. That might also allow you to add a launcher at times.

I don't think the bonus is the inline design as much as it is the flexibility of having an air compartment and a water compartment, each of which can be filled separately.

Anyway, good luck with the design! My hybrid will actually use a backpack, as I don't want to make the PC very small - I want massive output with decent shot time, so I can have some range and shot time. I'll have my cake and eat it too.

[DX]

I'm not sure how large I want it to be - the intent is a practical weapon that outclasses my old APHs in power and especially range. Since finances are tight, I've dropped my PPH projects and other APHs. This is the only project that is open, other than the Death Cannon. I've actually been considering using the Ruta Cannon as the pc, since we have to cut it up anyway [to double up the piston]. It can easily be converted to function as a water gun and not a cannon. The schrader valve and bleed valve are already there as well, so might as well use them.

However, a 3" pc would need a backpack, otherwise the gun would be really unwieldy. I'm not sure if I want to blow more money. I have the parts for an onboard, but I'd need cellular core pipe and more fittings for a backpack.