help a noob out :)

[JDAX23]

ok and if i were to change the barrel to 1.5 or smaller i would just have to make the barrels longer right?

[jackssmirkingrevenge]

You wouldn't have to make it longer, but you can afford to make it longer, meaning that for a fixed chamber size it will give you higher velocity and a quieter shot

[JDAX23]

haha ok i like the higher velocity but im kind of partial to loud noises if you know what i mean... so when i shoot it and hear it i know its powerful lol but for greater performance i guess i can let that go

[jackssmirkingrevenge]

If you want to make it powerful *and* loud, you could increase the chamber size to several times the barrel volume - but if you're filling it by hand, this will obviously take you longer to pump.

In short, make the barrel as long as you're willing to live with regarding aiming and storage, and make the chamber as big as you're comfortable pumping to your maximum pressure.

[JDAX23]

ok ya i want it to be as powerful as i can and the noise is just an added bonus but this is mainly for power and distance cause my friend thinks his little combustion will beat mine and i know it wont but i wanna blast his away lol... and i have a quick question since im new to this... the bigger the chamber, does that mean i can fill it to a higher psi or do i just go based off of the rating on the pvc like sch40??

[jackssmirkingrevenge]

Don't worry, such a launcher will out-perform a combustion big time

The size of the chamber has nothing to do with maximum pressure - if your pipe is rated to say 260 psi then you should never exceed that figure, no matter how large or small the chamber is.

[Hubb]

Don't worry, such a launcher will out-perform a combustion big time

The size of the chamber has nothing to do with maximum pressure - if your pipe is rated to say 260 psi then you should never exceed that figure, no matter how large or small the chamber is.

Correction: Don't exceed the rating on the lowest rated part which, in your case, will probably be the valve. Most sprinkler valves are rated to around 120 psi or so. It should take a little more than that but don't push it. But don't worry. If it fails, the diaphragm is more likely to break (releasing the air) than the sprinkler valve rupturing.

How do you plan on pumping up the chamber? If it is a hand pump, you may have difficulty seating the valve, that is, if the chamber is of a significant size (example: I had a 2" chamber that was 20" long and I had to push it hard to seat the valve with a hand pump).

[JDAX23]

ok ill try to remember that when pumping it up lol so i dont die... but i have a bike pump so ill use that but i wanna buy a nicer pump dealy so it will fill faster and to a higher psi...so for more power definately get a bigger champer right?

[Hubb]

LOL

You know, I just realized. You've asked that question, like, 7 times now and it has yet to be answered.

Well, I'm not going to answer it either.

JK - yes, to an extent

[JDAX23]

haha ya i know lol sorry... but ok thanks very much lol dude when i read the "Well, I'm not going to answer it either. " i was like ummmm?? lol

[Hubb]

Something I learned with these things:

To me, pneumatics are easier to build than combustions. They tend to be more powerful as well. The only downside about them is that (the one's I've built anyways) tend to cost more than combustions.

Now get this thing built and posted!

[JDAX23]

haha ya im beginning to find out that it will indeed cost more... seeing as how my combustions were pretty easy... just two nails and an ignitor... now for a pneumatic i have to buy a sprinkler valve and mod it, a blow gun, schraeder valve, air compressor lol but i think it will be worth it and ya im off to home depot to get at least the valve and the blow gun and see if they have all the pvc i need