Upgraded Pneumatic Marble Sniper

Mitchza89 · Thu Feb 22, 2007 8:10 pm

Hey guys, this is my second Pneumatic. I only just build it so at the momment it looks quite "Ghetto" without a decent paintjob and an overall clean up of the gun. Alot of people are gonna give me flack because im using a coke bottle as the chamber....but, I wanted to come up with a Marble Sniper that required absolutely no glue. So I came up with the idea to use Poly Pipe and fittings. Every piece on this sniper screws together which made it very easy to and quick to put together plus not to mention cheap. All up with all the parts, it probably cost me 30 bucks AUD. It fires at roughly 500 feet per sec at the momment (I have a really cheap Irrigation Valve that has a slow opening time plus the blowgun doesn't vent all that quick) so nothing special but well and truely good enough to destroy cans from a distance. I've got a better valve on the way. I'll get some good damage pics asap.

Thanks alot for looking,

Mitch.

Scope · Thu Feb 22, 2007 9:10 pm

That looks good... The only unsafe part might be the schrader in the bottle...
I like the blowgun you used

Mitchza89 · Thu Feb 22, 2007 9:24 pm

Its a Tubeless Car Tire Shrader Valve. It's stuck in there so tight, I can't even get it out. I've never had a problem or a blow out

Thanks for the comment mate.

noname · Thu Feb 22, 2007 9:35 pm

It looks ghetto? I have no idea what you're talking about, that thing is awesome, and looks great. Soda bottles are rated to 160 psi, so you shouldn't have a problem anyway.
Why is the blowgun in that position? Looks kind of awkward to shoot like that.

Mitchza89 · Thu Feb 22, 2007 9:43 pm

It's actually really comfortable to hold aye aye. I put it like that so I've got a curved grip like off a real rifle. I wanna get a small brass elbow so I can have the Blowgun attached the valve the right way round. I can imagine it'll be even more comfortable to shoot with the elbow. Yeah the soda bottles are great. I only go up to 115psi anyway so I got no hope of killing myself

haha. Thanks for the comment mate.

shud_b_rite · Thu Feb 22, 2007 11:27 pm

Are soda bottles really rated to 160psi? where did you get that information from?

By the way awesome gun, I like the simplicity.

Killjoy · Thu Feb 22, 2007 11:33 pm

A lot of people have tested them, me being one, and that 160psi is generally the burst pressure of most bottles, but it is wise to stay in the 100-125 psi range.
Anyways cool cannon, i like how every thing screws together. Most people just end up glueing their bottles into/to a piece of pvc pipe.

Mitchza89 · Thu Feb 22, 2007 11:45 pm

Thanks alot the comments =] Yeah i really don't see why people need to go over 125psi anyway....Thats more then enough to get the most out of your pneumatic. I'm sure you will get some small increases in power and distance if you pump it up a hell of alot more but it isn't worth it.

Killjoy · Thu Feb 22, 2007 11:50 pm

The bottles are cool when they explode though (unless they go off in your hand, nothing like having to do stitches by yourself). What brand of sprinkler valve did you use?

Mitchza89 · Thu Feb 22, 2007 11:53 pm

I wouldn't have a clue what brand it is aye. It was just a El Cheapo' valve that I got from my local hardware place for 14 bucks australian. I'm sure I would get much better results with a better quality valve, but for the time being, it works great.

Killjoy · Fri Feb 23, 2007 12:02 am

Alright just wondering.

joannaardway · Fri Feb 23, 2007 4:17 am

Soda bottles are not rated to xxx psi - it has no rating printed on the side, so it is not rated.

It is "safe" to xxx psi - not rated. It annoys me rather when people mix the two definitions up. Unrated and safe do not have to go hand in hand.

All rated materials are safe.
Not all safe materials are rated.

Onto advisable pressures. You can get major power boosts from more pressure - 125 psi is actually quite limiting.
Power is largely proportional to pressure (with a quick opening and high flow valve). So, if you double the pressure, the muzzle energy roughly doubles as well.

noname · Fri Feb 23, 2007 11:00 am

It is "safe" to xxx psi - not rated. It annoys me rather when people mix the two definitions up. Unrated and safe do not have to go hand in hand.

After hearing senior members of this site and spudtech say that bottles were rated to 160 psi, I assume they are, and pass it on. In other posts, I guess I'll say they're safe to 160 psi. Thanks for clearing it up.

Killjoy · Fri Feb 23, 2007 12:47 pm

All rated materials are safe.
Not all safe materials are safe.

What? How safe materials not always safe? That goes against their definition.

joannaardway · Fri Feb 23, 2007 1:44 pm

B*llocks - I screwed that up. Read again for what it was meant to say.

Technically "rating" is something that a company defines it's products as being safe for.
I don't imagine Coca-Cola (or any other company) sits down and wonders:
"Hmm, should we rate our plastic bottles for pressure, in case a customer wants to re-pressurise it for an air cannon?".

The figure we have is something spudders have tested and have decided is probably safe, but we can't "rate" it, as we aren't the manufacturers.