SpudFiles

This is my latest creation. It is a fairly simple sniper derived from a conglomeration of various designs on the site. The gun features a typical 1" orbit sprinkler valve (blowgun modded), a poor man's breech, and a 10x optical scope. The chamber is made of 2" pvc which is reduced down to 1" for the elbow and tee, then finally down to 3/4" for the barrel. The stock is also made of 3/4" pvc and is blocked for safety. My goal was to create a powerful yet very safe gun that looked clean and professional, therefore all parts of the gun are made on nsf-pw fitting, schedule 40 pvc, and the gun was finished in matte black paint. According to ggdt it is capable of shoot a paintball at about 650 fps. Primary ammo includes: paintballs, marbles, "c" batteries, "aa" batteries, and bolts.

nice very clean you defiently did your research good job amaizing looking gun.

Thank you for your kind words, this is my second gun but my first sniper. I am considering adding a propane fill to it so i don't have to lug around my air compressor or bike pump, but I'm having trouble calculating whether or not I'd get a decent amount of shots or not because the ideal gas law does apply due to the fact that the propane is stored as a liquid. Is there anyone who can help. Everything I've googled has been over my head.

Nice looking gun looks similar to my current project. What is the actual definition of sniper cannon cause it is tossed around quite a bit and i have yet to see what makes a sniper and what doesn't.

DinerKid wrote:What is the actual definition of sniper cannon cause it is tossed around quite a bit and i have yet to see what makes a sniper and what doesn't.

There is no strict definition. Some people will tell you that it shouldn't be used at all, because a sniper is the person, not the rifle, and that it's nowhere near accurate enough anyway. Some don't care.

About the only consistency is that it tends to mean that it's fired with a reasonably direct trajectory at targets rather than going for lobbed distance shots.

That looks beautiful!
If you know the MASS of the propane in your tank, you can probably find the moles of propane, thereby finding the total amount of propane you have. Using the ideal gas law you can probably find the total number of shots you can get. I think this'll work, but there are also additives that make the propane smell. I think the mass recorded on the bottle though is the mass of just propane, and even if the additives are in the mass, they're probably negligible.
In case you didn't know, propane has a cooling effect when it vaporizes, so it's probably not a good idea to let the liquid flow into the gun directly since it's PVC. Propane also preforms worse than air since it's dense, and you can't get as high pressures due to its vapor pressure. I myself am working with propane as a pneumatic source though, and I think that with your chamber it should work decently well.
Also, if you can, I'd recommend upgrading the barrel to schedule 80 PVC since it fits PB's better. Menards carries it I think.
Also, if you can you might want to add a barrel support.

Overall though it looks really slick, and VERY proffessional. Nice work!

thanks for your help noob of noobs. I already understand the problems of vaporizing a compressed liquid, as i have played paintball for many years. I'll look into calculating the moles of propane, I hadn't thought of that. I guess need to know the weight of an empty propane tank as well as a full one in order to calculate it though. As far as pressure, I hardly ever shoot above 80 psi so propane should provide adequate pressure. My play was to have a portable propane tank in a fanny pack with a regulator and a remote coil going into the gun. Do you have a link to your build? Unfortunately we do not have Menards here in FL, i checked at home depot and lowes but neither had schedule 80. They did however have some sdr pipe. Next time i go I think I'll bring a paintball and test fit various pipes. Between the sdr and cpvc pipe selection there has to be something that fits a paintball better. Once I get a tighter fit I plan on adding hop up as well.

Ragnarok wrote:

DinerKid wrote:What is the actual definition of sniper cannon cause it is tossed around quite a bit and i have yet to see what makes a sniper and what doesn't.

There is no strict definition. Some people will tell you that it shouldn't be used at all, because a sniper is the person, not the rifle, and that it's nowhere near accurate enough anyway. Some don't care.

About the only consistency is that it tends to mean that it's fired with a reasonably direct trajectory at targets rather than going for lobbed distance shots.

Doesn't even have to be a rifle, marksmen were around before rifling.

I wouldn't call anything here a snipers weapon because what exactly are you doing with it that compares to a sniper? (hiding in the undergrowth because it's illegal where you are doesn't count).

Milplay gets into everything though so call it what you'd like it to be. There are PVC LAW cannons out there and I don't recall ever hearing anything about their poor comparison to the real thing.



Good work on the cannon

how did you cut the stock off from the rest of the cannon, air-wise?

With just a little bit of sanding, a 3/4" cap fits into a 1" Tee

K-Dawg- wrote:thanks for your help noob of noobs. I already understand the problems of vaporizing a compressed liquid, as i have played paintball for many years. I'll look into calculating the moles of propane, I hadn't thought of that. I guess need to know the weight of an empty propane tank as well as a full one in order to calculate it though. As far as pressure, I hardly ever shoot above 80 psi so propane should provide adequate pressure. My play was to have a portable propane tank in a fanny pack with a regulator and a remote coil going into the gun. Do you have a link to your build? Unfortunately we do not have Menards here in FL, i checked at home depot and lowes but neither had schedule 80. They did however have some sdr pipe. Next time i go I think I'll bring a paintball and test fit various pipes. Between the sdr and cpvc pipe selection there has to be something that fits a paintball better. Once I get a tighter fit I plan on adding hop up as well.

Most modern propane fill places fill with a meter, much like a gas pump. In the old days (really old) Propane was sold by the lb. The tank was weighed empty and then the proper amount was delivered to prevent overfilling. Nowdays the overfill and just before that the 10% vapor valve was used to tell when it is full.

The empty tank weight is referred to as the tare weight. The tare weight of many tanks is still listed by the manufacture and is often stamped on the tank. That way you can find the amount in a partially used tank by weight.

Reference below;
http://www.propane101.com/propanecylinderfilling.htm

Thank you very much Technician1002!

FYI tech,...It's still sold by the pound in Canada. Topped off my trailer tank yesterday...13 pounds worth.

Behind the times or maybe a little backward we is.

K-dawg, Nice job. Looks like it would be a hoot to plink with. :thumbup:

Nice work,reminds me of my old pnuematics of which I dont use anymore as I too got tired of having to pump up the chamber with a pump all the time! . Does the breech leak much air,I never had any luck with such feeders as they allways leaked so just muzzle loaded.....

Gippeto wrote:FYI tech,...It's still sold by the pound in Canada. Topped off my trailer tank yesterday...13 pounds worth.

Behind the times or maybe a little backward we is.

K-dawg, Nice job. Looks like it would be a hoot to plink with. :thumbup:

Filling by weight has lost favor in the US. Most Propane is sold by the gallon. Sometimes when there is a problem, Propane gets contaminated by oil. Over time oil can build up in a tank and prevent proper filling using weight. Most Propane is clean, but I had a batch several years ago during a cold spell. The dealer was low, so when pumping liquid, I got a bunch of oil in my fill. It oozed out my torch nozzle and the flame spit yellow streaks, often plugging the orifice. It was long enough ago that the tank did not have an OPD valve. I turned the tank over in a field and dumped it, charged it with a couple more pounds to rinse and dump again. The oil held a large portion of the stench they put in propane.

After the purge and rinse, the tank was good as new. Now before I buy Propane, I always check their gauge so I don't get the floating oil.

Just an FYI for those who buy Propane. Never buy of the end of a tank. Oil floats on Propane and is the last out on liquid delivery. Unless purged, this oil remains in the tank.

I am not the only one who has seen this.

http://www.yarchive.net/car/rv/propane_tank_oil.html

They saw it on a new tank. Bummer. I saw it on an old tank and had no problems for years. The contamination was sudden and attributable to one fill.