Page 1 of 2

first air gun!!

Posted: Sat Jul 23, 2011 5:03 am
by barrius
hey people, a month or so back i found a blog where a guy made a type of pneumatic marble rifle. i thought it seemed pretty cool so i thought id try making one for myself, but a different version. after making it i found this website which seems a good place to show it off :P ive been browsing here for a few weeks and have some good ideas for my next gun, and i even tried making my own pengun but i cant get it to work properly.. anyway, heres my first gun. the barrel is half inch polypipe, roughly 2 feet long. there is a hexagonal shaped connector i put on the end as a sight. the barrel is connected at the other end by a brass connector to a 3'4 inch ball valve, which is connected to a 3'4 inch brass tee piece with an end cap with a schraeder valve in it. the other end of the tee is epoxied into a 750 ml alloy water bottle which i use as an air chamber. there is a wooden stock attached to the barrel by copper pipe brackets, the stock is a 2 piece stock with a handle of a small bike pump attached to one end and the body of it to the other end closest to the air chamber. the stock and body of the pump closest to the air chamber cant move, but the stock and handle of the pump is able to slide up and down the barrel, to make it pump action and have an air supply and the gun as one unit. but usually i dont attach the smaller pump and just use a bike pump. for ammo i use anything that will fit in the barrel, but mostly supasplat paintballs. i fired a fishing sinker at a brick wall approx 20 metres away and it ricoched straight back onto my roof lol. so its pretty powerful. i usually fire it around 120 psi, but i have a shock valve coming soon to test out higher pressures.[img]C:\Users\barrius\Pictures\2011-07-19[/img][/img]

Posted: Sat Jul 23, 2011 5:05 am
by barrius
i dont know how to upload pictures lol it kept saying they're too big

Posted: Sat Jul 23, 2011 5:11 am
by daniel0663
Welcome :)
i dont know how to upload pictures lol it kept saying they're too big
Try uploading you're pictures on Photobucket or Imageshack.

Sounds like a good effort for a first. :wink:

Re: first air gun!!

Posted: Sat Jul 23, 2011 5:28 am
by Crna Legija
barrius wrote:the barrel is connected at the other end by a brass connector to a 3'4 inch ball valve
WOW :shock: A 3 foot 4inch ball valve that's massive :lol:

edit: Read though this should help you post pics

Posted: Sat Jul 23, 2011 5:40 am
by barrius
3 quarter inch.. haha cheers guys!
:lol:

Posted: Sat Jul 23, 2011 5:49 am
by Crna Legija
barrius wrote:3 quarter inch.. haha cheers guys!
:lol:
3/4'' lolz

Posted: Sat Jul 23, 2011 8:17 am
by barrius
lol anyway heres the picsImage

Image

Image

Image

Image

Image

Image

Posted: Sat Jul 23, 2011 8:38 am
by Doctore
Thats nice!!! :D
Are you planing to add trigger mechanism.
Any damage pics???

Posted: Sat Jul 23, 2011 8:45 am
by barrius
hey, yeah i was planning to add a trigger sometime, ive got a bolt going through the lever on the valve, my plan was to attach a spring to that, and the other end of the spring to the stock, so when the valve was shut it would stretch the spring. then build a crossbow like trigger set up to hold it back.

no damage pics yet as ive only fired paintballs and the sinker at a brick wall, but ive got some alluminium tent stakes shaped like mini star pickets that fit perfectly in the barrel, soon as i find a place to shoot ill take some decent damage pics lol. it also fires AA batteries really well. and these miniature bottles of glitter i bought that fit perfectly in the barrel make a nice sparkly cloud when they hit a wall :lol:

Posted: Sat Jul 23, 2011 8:56 am
by saefroch
IMHO, you've got that ball valve on backwards.

Posted: Sat Jul 23, 2011 8:59 am
by barrius
i wanted it to open forwards so i could attach a spring to it for the trigger set up.. do u think it would change the performance if i had it around the other way?

Posted: Sat Jul 23, 2011 9:01 am
by Crna Legija
Be careful with those water bottles, don't go passed 200psi, they have very thin aluminium walls.

Posted: Sat Jul 23, 2011 9:04 am
by barrius
cheers yeah i notice it heats up a lil at 120 psi. what would be a good high pressure substitute for something like this? i was thinking threaded brass plumbing fittings?

Posted: Sat Jul 23, 2011 9:39 am
by jackssmirkingrevenge
Crna Legija wrote:Be careful with those water bottles, don't go passed 200psi, they have very thin aluminium walls.
I think 200 psi is very generous, I wouldn't trust them past 50.

Posted: Sat Jul 23, 2011 10:31 am
by saefroch
barrius wrote:i wanted it to open forwards so i could attach a spring to it for the trigger set up.. do u think it would change the performance if i had it around the other way?
Gotcha. It's not hampering performance, just ergonomics right now.