Coaxial pneumatic Chamber size V.S. Barrel size

[Leonard]

Hello!
I'v been lurking around this website for a few weeks, trying my luck at building a few pneumatic launchers with the help i found here. The time as now came that i shall subscribe to ask you guys a quick question.

Im considering building a coaxial marble shooter (with a semi-auto loading mecanism inside the chamber), barrel will be 3/4 inch and pilot 3/4 inch sprinkler. Considering im looking for reasonable power but nothing excessive, would i be better off with a 2 inch chamber or a 1.5 inch?

I'v previously made a few launchers using a sprinkler valve (semi-auto loading mecanisme has been designed on a sprinkler valved launcher) but i now wanna try piston, hence this question.

Thanks!

[jackssmirkingrevenge]

(with a semi-auto loading mecanism inside the chamber)

A diagram would be nice

Considering im looking for reasonable power but nothing excessive, would i be better off with a 2 inch chamber or a 1.5 inch?

If you're making it semi-auto, then presumably you'd want more than one shot per chamber fill, so a bigger volume is going to give you more shots.

[Novacastrian]

What JSR said very politely then was "If you show us that you have even the most basic knowledge in the construction or theory of said cannon, we will try and help you as much as possible".

Was i close to the mark jsr?

Welcome to spudfiles Leonard.

[jackssmirkingrevenge]

Was i close to the mark jsr?

In a nutshell we can't have advanced concepts being thrown around without a measure of substance, right

[Novacastrian]

Measure is always a good thing

[Leonard]

You should not have to worry, im not a 14 year old boy who's gonna blow up his entire family in little pvc pieces... ^-^

As you requested, i took a few pics of the mecanism i spoke about. I have NOT designed or invented anything and i do not pretend i did. I simply copied the GB semi loading mecanism into something smaller and added a few things (like a second spring to smooth the comming back of the bolt).

Here :



[albumimg]364[/albumimg]

Bolt opened

[albumimg]363[/albumimg]

Bolt closed

[albumimg]360[/albumimg]

Full view

[albumimg]361[/albumimg]

Opened up



EDIT : Oh, well the images in the album dont seem to work... if you're curious, just go in the album and you'll see i'v uploaded the photos.[/list]

[jackssmirkingrevenge]

You should not have to worry, im not a 14 year old boy who's gonna blow up his entire family in little pvc pieces... ^-^

It was the standing upside down next to a fire that worried me

Your launcher sounds interesting but I still can't see the pics... can you at least give us a link to the album?

[Leonard]

I cant seem to put the pictures in my post... but they are in the album if you're curious.
I feel i supplied suficient proof of my non-stupidity, so i'd be very glad if you could answer this quick question (Cant seem to get the answer from ggdt) :
To achieve the best barrel : chamber ration in a coaxial, should i make the chamber 2 inch or 1.5 inch?

[bigbob12345]

You should not have to worry, im not a 14 year old boy who's gonna blow up his entire family in little pvc pieces...

Im 14 and I take greater safety precautions than most people on this site so Ill take it you are refering to the type that play around with them on youtube that dont know anything about pressure rated parts or C:B ratios or anything else.

And the answer to your Question is 2in in my opinion because the bigger the chamber the more power and if you want a better ratio just make a longer barrel but 1.5in should provide suffeciant power to so it really doesnt matter that much.

[sjog]

leonard .
2 or 1 1/2" will not matter. Experiment . K.I.S.S.

[Leonard]

Thanks! I'll be trying my luck... anyone have any idea how to put images from the album into a post?

[MrCrowley]

From the spudfiles album?

If you mean from like photobucket or something, just right click on the image, go to properties, highlight the URL, and copy into your post, then highlight the URL of the image in your post, and click the 'Img' button.

[jackssmirkingrevenge]

If you're on photobucket or similar, make sure your album is public and not locked.

[Leonard]

I mean't the spudfile album, sorry. I copied the bbcode ([albumimg]*364*[/albumimg])and activated the bb in the reply, but it still does not work. I'm not realy computer wise...

[jackssmirkingrevenge]

can't you just paste them in the thread like this