My first pneu evolved.

[Vb_happiness]

This is a timeline of my gun, with a few damage shots at the end. I started with a simple design of a solenoid gun with barrel and chamber in a straight line. No photos

Then moved to a short "U" shaped ball valve operated mini gun.



Next I added an "L" between the "U" and the chamber. Also experimented with silencers at this stage. I live next to a hospital and other that the obvious there is also coppers driving past everynow and again.



And then the other night I went down to Bunnings and got a hand full of T's and 90deg's and another length of 25mm pvp pp and still using my original chamber that I fitted with a 25mm Male on the 50mm cap with 1/2 a 25mm connector on the inside to secure it. I came up with my rifle design, it is pretty chunky I think I might use some bends for my next design to get a better fit under the arm.






Now for some damage shots. Only using paintballs at the moment.






-Conclusion- Don't think my dog will be drinking out of this anymore.


-Conclusion- Need something thicker than 3mm MDF.


-Conclusion- It takes 3 paintballs to break out the bourbon.

[spudkpi]

Is the stock part of the chamber? If so your constricting the flow like a mother...

[Vb_happiness]

How does it constrict the flow?

[M3NT4L]

Nice damage shots, if you make the chamber/resevoir bigger you will have much more power.

[Vb_happiness]

I fill it to on average about 100psi it is going pretty well. I'm not sure how I would Increase the size of the chamber, if i did it would be more chunkier than it already is. I have been told by a mate that if i block the path between the two "t" sections it would better the flow is that true?

[MrCrowley]

Yeah it is true,because of all the turns the air takes before getting to the valve.Thats why when people build a Pneumatic sniper they block of the stock but they have a bigger chamber then your so tehy dont need stock to act as a chamber as well.

[Vb_happiness]

I suppose I could Make the Chamber a bit longer and i look into increasing the diameter of it aswell.

[MrCrowley]

for alot better performance make the chamber the same length as your barrel or upgrade the chamber to a bigger diametere and keep it the same lenght and you should be fine

[Vb_happiness]

Ok, it seems to go pretty hard at the moment so your saying increase the volume and it should increase the exit volocity of my projectile?

[MrCrowley]

yeah, do you have GGDT? with GGDT you can fiddle around with volume of your chamber and the dimensions of your gun to find the best velocity or distance for the best value.like increasing the chamber volume but not the barrel will put the fps up but the distance will relativly stay the same unless you make your barrel longer.you can download GGDT from here:
http://www.thehalls-in-bfe.com/GGDT/index.html

[killagorrila99]

wow nice gun, made one just like it. leaked teribly, thankfully ur not having the same problem

[Vb_happiness]

Nope no dramas, only my dust gun is royally f*cked, it took a few goes to get my chamber worked out, what it is, is a 50mm cap drilled out with a 25mm male glued in with a 25mm connector at the back not the best design but it works pretty well, it was better than my brass nipple just cut the pvc. Its all good now, its not functional at the moment but im just gonna pop down to bunnings on the weekend and grab a new dust gun.

[THEMOST]

Why would all the turns restrict air flow? Only an idiot would say that because the air is already pressurized in the tube. It doesnt make any difference! if it did than any piston valve wouldnt work worth crap because the air would be required to take a 180º turn (coaxle) to blow out the barrel. Obviously that is not true so therefore whoever says that making bends in you air chamber will hurt performance is a dunce.

Dont fall for their stupid trix Mr. Happiness theyre full of crap. Make you gun however you want.(although i must say that thing isnt lookin soo hot right now, you really need to make it more compact.)

[Insomniac]

If you are going to say it doesn't constrict flow, wit untill you know what you are talking about. Air is a fluid, and when a fluid changes direction it loses speed. Piston valves work so well because the lost performance from the turns is way less than the performance gained by the high opening speed of the piston. It's having the air go through unnessisary turns that is a problem.

[frankrede]

Hmm, not sure if hes right or not but air still goes thrugh thse parts, by the time it matter though the projectile is already exited the barrel so maybe he is right.