SpudFiles

i´m going to make a pneumatic marble or bb gun, but, i dont know what is the better chamber, a pvc pipe or a 500ml cola bottle ...

A pressure rated (Schedule 40\80\120) pipe with pressure rated fitting is much better than a cola bottle, but it will cost you some more...

A Cola bottle is sufficient, and if it fails, it will probably just tear in half without putting you in much danger...

Keep in mind that it can explode though... A 1 liter bottle can hold decent pressure though.

Use the pipe. It will be able to hold a lot more pressure and is more customizable than a bottle.

Just spend a couple extra bucks and go with the pipe

but i dont have a compressor, i will use my bike pump....
how much PSI can i make with that ?

However much the pump is rated for. Considering a marble gun, the chamber isn't going to be that big. With that considered, I can pump my pneumatic up (2" x 12" chamber) to 80psi with only 5 strokes. Your chamber will probably be smaller than that.

If you have any power in your arms or any weight in your body you can pump it or even "jump" while pushing down with your arms to at least 80 psi...

You can also build your own high pressure hand pump. Like this one. Is this going to be a 'sniper' type gun?

nightshot wrote:i´m going to make a pneumatic marble or bb gun, but, i dont know what is the better chamber, a pvc pipe or a 500ml cola bottle ...

I really wanna slap you for asking that question.

BigGrib wrote:

nightshot wrote:i´m going to make a pneumatic marble or bb gun, but, i dont know what is the better chamber, a pvc pipe or a 500ml cola bottle ...

I really wanna slap you for asking that question.

Don't taze him bro! <a href="http://plugin.smileycentral.com/http%25 ... /page.html" target="_blank"><img src="http://smileys.smileycentral.com/cat/3/3_12_14.gif" alt="SmileyCentral.com" border="0"><img border="0" src="http://plugin.smileycentral.com/http%25 ... e.gif"></a>

Or if you would have a car available where you are shooting you could get a fairly cheap DC power Air pump, that hooks into your car cig lighter. Thats what I use to pump up my water rockets. And I believe you can get them fairly cheap to. I may be wrong tho. But I dont know if you have access to a car or not. Just a suggestion though.

try the bottle at first if it is the right thing for you use the same barrel and valve and upgrade to a pvc or steel chamber. i would go with steel or copper on a gun that small bechause then you can use a car DC compressor and use 300psi in it. and steel are not that much more expensive than pvc and in my opinion it is a better option since you may be unlucky and drop it.