SirBlastalot

I was playing around with my new longshot, seeing if I could maybe get the scope lined up/marginally useful. I pulled back the bolt, the stock collapsed, and I stabbed myself in the eye with the friggin' scope. Now I have a black eye.
I'd read about the stock collapsing thing, but I'd thought that would only be a problem with an overpowered spring, not a stock gun. I think now I'll just drill a hole through them both and stick a metal rod in there. I have a black eye now.

So a friend and I are working on a project (several projects, actually) where we'll make a gun something like this:



It will be mounted on a tripod, with an electric pump. The pump we're using is designed to run off of a car's 12v battery, but we're going to use an adaptor to step down the 220v AC wall current to 12v DC. This design is really simple, as my friends and I are all newbies.

The way it works: We let the pump run untill the air resivoir is at an appropriate pressure. Then, just open the valve and air will continually stream out. We're going to pump up the pressure to something signicantly higher than the pressure nerf guns normally use, because we intend to lose alot via the feed mechanism. We'll either use a gravity-fed clip, or construct a chain with an electric motor to push darts in front of the stream of air. It'll obviously be very inefficent.

My question is this: What pressure do nerf guns normally fire at? I was remembering it as something around 15psi, but Capt. Slug mentioned 40psi in one of his recent posts. We had only planned on pumping up the tank to somewhere around 40-60 psi...

So my friends and I decided that having an actuall rocket-launcher would be cool, instead of the nerf rockets. (That are not technically rockets, just extra-large darts.) We're going to make some large, styrofoam rockets and stick a C02 cartridge in the back. The thing is, we lack the mathematical know-how to figure out how fast one of these rockets would get going. Would anyone with a physics background be willing to help us out? My dad calculated that the CO2 will be expanding from about 50ml to around 5L. Anymore variables you need me to observe, just let me know

I wouldn't normally post this here, but before I started I wanted to make sure this isn't going to be going so fast as to be dangerous.

So I had this idea while riding on the bus one day.

Allthough I'm sure there's a better gun out there to do this with, let's just pretend we're going to do this with a Longshot, modded with Capt. Slug's Shotgun Foregrip. You attach a grooved rod to the grip, and a design similar to K Barker's Clip design. The diffrence is that this way, with each cycle of the grip, the gear is engaged on the pull backwards (moving the clip up) and disengaged on the push forwards. This way, using some fiddling with the gear ratios, you can cycle the clip upwards with each motion you'd normally do. (Obviously, the LS already uses magazines, but the same idea should be applicable to other guns)