[TopCityGear] was trying out a piece of PVC as a blow gun barrel when he thought he’d try to give it a little more power than what his lungs could put out. What he came up with is this air-powered Nerf gun that definitely leaves a mark. The video after the break is a show-and-tell, a build log, and finally a demonstration of its power. He adds a nail to a Nerf dart and drives it through a board, then leaves a huge welt on his poor friends chest with a plain old foam dart. It reminds us of those riot guns that shoot bean bags.
The air is stored in that twelve-inch PVC reservoir. On the rear cap there’s a Schrader valve for pressurizing the tank with a compressor or even a bike pump. The grip is a gutted cordless drill whose battery doubles as the power source for the electric sprinkler valve which fires the gun. The screw fitting just in front of the hand grip lets him remove the barrel so that the projectile can be inserted.
This reminds us of that gun which shoots water-filled ping-pong balls.
[via Hacked Gadgets]
Cool. Similar performance to the recent JT Splatmaster single pump guns (no air required).
http://www.sears.com/kee-jt-splatmaster-z200-paintball-shotgun-50-cal-red/p-SPM6138326605P
Would be faster to muzzle load. Make a ramrod that has a stop on it so the dart is pushed in to the right depth.
I did that with alfalfa pellets in my Daisy Red Ryder BB gun. :)
I used match sticks, straight pins, and paper feathers, to make darts to shoot out of my Red Ryder BB gun. Unfortunately that lead to a time period of Jr. High boys making all sorts of homemade darts, and their inappropriate use. the guy in the video volunteered(or his beer volunteered him) for the bruise, back then there where kids to didn’t volunteer to bleed from hand thrown darts.
Very cool. The air reservoir is definitely much larger than necessary, and he’d gain a bit of muzzle velocity by modifying the sprinkler valve to actuate pneumatically. But still very cool.
The air tank is NOT to large. The barrel length is not long enough to take advantage of all the pressure. I have a friend who experimented around quite a bit with air guns such as this, and he found that the barrel length is a huge variable, with both accuracy and range; but yes, this is very cool.
While pressure is a consideration so is the volume of gas used, and that was somewhat mentioned in the youtube contents. In the event I remember correctly when it come to modern gunpowder, there are formulations to use with shotguns, rifles or handguns. The burn rate/time being the difference. To put a fine point on this gun, having a circuit that would hold the valve on for a certain amount of time each time the trigger is pulled to fine tune it to any barrel length or diameter. Theoretically it could be adjusted to mimic a lung powered air gun. Being gentler on the Nerf darts, and getting more shots from a tank of air.
Shut tp
PAINT BALL SHOT GUN! just make sure they don’t grip the sides of the barrel or you just end up spraying paint everywhere.
it royally pisses me off to see people using PVC for pressure tanks. Just hope that it never explodes because if it does the shrapnel will kill someone.
Why? He specifically says to make sure it is PVC that can handle pressure. And on the pipe it says 220 psi. Then he states he’s using 30 PSI for the test shots we see…
Water pressure and air pressure are NOT the same. True, they exert the same amount of force internally but water doesn’t (appreciably) compress. Air does. When the PVC cracks or breaks (dropping it, a sharply pointed impact, etc), it shatters and the air expands and it throws sharp PVC shards everywhere. PVC pipe manufacturers SPECIFICALLY label their products as not being suitable for use with air for this very reason. Use a more appropriate material, please.
I spent 20 years plumbing PVC and CPVC into industrial water systems carrying water at over 150 psi. Schedule 40 PVC, at room temperature, is fine up to it’s rated pressure when constructed properly.
While it’s true that ANY pressure vessel can fail catastrophically under the wrong conditions, making a blanket statements about PVC not being usable for pressure tanks is a great way to demonstrate ignorance.
PCV is not suitable for AIR pressure because it shatters when compromized. That’s the point. A pressure vessel designed for expanding gasses must be tough so as to not form shrapnel.
Even glass can withstand a lot of pressure, but you don’t want to be anywhere near when it bursts.
And thinking that PVC is suitable for air pressure is a great way to demonstrate ignorance.
Consider this:
P=F/A
Pressure is equal to force over area. Change the area, change the force.
E=F*d
Potential energy is equal to force times distance moved.
You can calculate the stored energy using those equations. For an incompressible liquid, volume (and hence area) cannot change, so there is _no potential energy stored_
Can you see where this is going? It’s all about what happens when the pipe fails. One will spring a leak, the other rips itself apart.
And lets be honest, the pipe you were using wasn’t going through near the abuse that this guy’s air reservoir does.
i always use some duct tape and plastix/dip paint on the pvc air tank. Makes me feel better about the shrapnel not flying the day i over pressurize..
LOL any old crystal ball will do when it comes to predicting when the using PVC with compressed air debate is going to occur in the Hackaday comments. ;)
came for the OMG PRESSURIZED PVC.
leaving satisfied
Right. Just like how when we get a story about making explosive rocket engines you get a lot of people talking about how that’s a really bad idea.
Mostly because they’re both REALLY BAD IDEAS.
The air is stored in that twelve-inch PVC reservoir.
When referring to PVC pipe, it is traditional to refer to the diameter not the length when leaving out any descriptor – or by stating that the measurement belongs to the length if describing the length and not the diameter. This gentleman is not holding a 12″ PVC pipe – he is holding a 12″ long PVC reservoir.
This not not unique, interesting or new… I built one of theese at 10 with a bike pump for portability.
OMG PVC under PSI!
I’m positive someone could post an article about one of the MILLIONS of DIY PVC pneumatic air guns throwing ‘flying shards’ into the builder’s face when it EXPLODED, right? I mean there just HAS to be at least a SINGLE article out there on the interwebs… right?
..no?
…huh.
http://www.personalinjuryattorneybostonma.com/2012/01/pvc-piping-explosion-injures-manufacturing-worker.shtml
http://www.justicenewsflash.com/2009/09/09/florida-construction-accident-lawyer_200909092071.html
http://beeradvocate.com/community/threads/redhook-brewery-employee-dies-from-exploding-keg-accident.14191/
http://www.killsometime.com/videos/8451/Homemade-Gun-Explodes-In-Kids-Face
There are PLENTY more.
You could have done this with a super soaker for cheap
Yeah well I’ve been the guy that had to pull PVC shrapnel out of his arm, luckily I only got my arm and not an eye or bystander. It is a bad fucking idea don’t do it.
this is not anything new or actually even that impressive sadly. we’ve been making these since atleast 2005 if you are going to post this atleast give credit to the original creator which was cxwq of the nerfhaven.com forums