SpudFiles

Well as the tille suggests this gun is pathetic, the marbles coming out of it cant be going more thn 250fps which is pathetic.
Anyways this gun was made from boredom, and is probably not even worth posting here but im posting it for the same reason i made it.

It was made out of some leftover scraps of 1/2in metal pipe and fittings.
and no comments on the ball valve as I dont see a reason to change it.

and the reason there is a 1/4in ball valve on it is because i did not have a 1/4in plug laying around so I used a ball valve I had on a gun I hadnt used in a while.

specs

chamber:4in of 1/2in metal pipe
barrel 28in on 1/2in sdr21(marbles are a little loose but paintballs are nice and tight)
operating pressure:100-200psi(will go up to 500psi once i finish me high pressure pump)
fill valve:shrader valve
valve:1/2in ball valve

pics

Heck, maybe I'll make something like that... Give me an excuse to shoot marbles in the city... Because my gun will be weak!

It really is weak
it cant even peirce two layers of cardboard at 200psi

Wow. Quite weak then ahaha.

in my opinion there is no such thing as a pathetic gun, if u take the time to build it then its worth posting. if you could get your hands on a longer chamber pipe i bet it will go kapow!

...In a good way, maybe...

I'd actually suggest a longer barrel. Since the opening time of the valve is so long, a longer barrel will allow better performance. Chamber volume to add to that would also be good...

And I wouldn't call it pathetic. I wouldn't want to get hit by a marble going 250 f/s....

I just GGDT'ed it and the barrel is supposedly unnessecarily long so i will shorten it. And my prediction of 250fps was almost excatly right as GGDT said it is 248fps.

supposedly if i replaced the ball valve with a burst disk then the performance will jump to 600fps
so i may go buy a 1/2in union

I actually might upgrade this gun a little because of the 600fps gGDT predicted

Whenever I use GGDT it always says the barrel is too long. I would just ignore it.

it says it is too lo0ng because it is so long that it is losing power
my current C:B on this is about .15:1 which is quite low