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Ball-valve AG w Stock

Posted: Sun Jun 24, 2012 10:46 am
by josephlys
Here's what I've been working on during my free time. A ball-valve airgun was simple enough to put together, without taking up too much time and effort. The stock isn't a solid piece, they're made from separate planks, I'm going to epoxy the handle, butt and foregrip together. I also need to shorten the ball-valves' handles and set up the trigger. Maybe paint it?

The barrel is .45 copper & the air-chamber is 1/2'' x 8'' steel pipe. Currently using 40gr+ naildarts @ 100psi. I hope I can find a good shock pump that doesn't leak and take it up to 150psi - 180psi. I hope. :P

1 question, if a ballvalve is rated at 150psi is it okay to take it up to 180psi to 200psi? 30-50psi pass the rated point? Is it safe? Will this damage the valve?

Posted: Sun Jun 24, 2012 11:32 am
by jackssmirkingrevenge
Consider spring loading the ball valve for better consistency and power.

I've used "domestic" grade ball valves to 800 psi without problems.

Posted: Sun Jun 24, 2012 12:45 pm
by josephlys
I will, I was planning to spring it open, this is gun is still unfinished. I will use a strong elastic instead of a spring, cause I can't find a spring lol. Just have to replace the bands when they wear out. I like the ball-valve's simplicity. It can be easily put together anytime.

I'll update this in more detail when the gun is finished. :D

Posted: Sun Jun 24, 2012 1:19 pm
by Labtecpower
self promotion yay! :D

your stock design is ideal to put this kind of system on!

Posted: Sun Jun 24, 2012 1:42 pm
by josephlys
Labtecpower very nice gun and trigger mech. I like the threaded bolt with the hook I'll see if I can find that, very nice idea I used to use just a bolt to hold the bands to my trigger for my previous one. Anyway thanks for the :idea:

I'm planning to use black zip ties. Should I spray paint it black or gloss it or... any ideas that would make it look better. Black paint would be an easy way out to cover up the zips and epoxy. Then maybe some designs, lol. :D

Posted: Sun Jun 24, 2012 4:21 pm
by mattyzip77
Cool simple design however I think it looks better without the wood,,,

Update

Posted: Thu Jul 26, 2012 9:14 am
by josephlys
update, sorry it took so long been busy. Anyway Finish putting together my ball-valve airgun :D
Image

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Shot into a wooden shelve, also tested on different hardwood boards @ 100psi I can get these darts 1/2'' deep. On softer variety/parts of wood It drives them almost 1''+ deep.
Accuracy -sigh- not so good. 4'' groupings standing offhand @ 10meters(30feet). With a rest I thought it would be much better but only improved slightly with 3'' groupings. I'm using 2'' naildarts (2.7g)
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Just need to juice it up from 100psi to 400psi, and shoot some bigger, heavier naildarts.

Posted: Thu Jul 26, 2012 3:14 pm
by jackssmirkingrevenge
Ah, much better :)

Given the random direction in which the nail darts will exit the barrel, I don't think you can expect much better accuracy than what you are getting with these projectiles.

You might want to consider a 1/4" ID barrel and use 0.25" airgun pellets for better consistency.

http://www.pyramydair.com/a/Ammo/Pellet ... ibers_0_25

Posted: Fri Jul 27, 2012 1:00 am
by josephlys
Here's a fiberglass paper cone I made to withstand high pressures. It's made by layering 3 layers of fiberglass tape atop a piece of paper.

Posted: Fri Jul 27, 2012 1:15 am
by jackssmirkingrevenge
What you need though is something to centre the nail in the barrel, to make sure it flies true.

Posted: Fri Jul 27, 2012 8:38 am
by josephlys
Another update: Made it a little lighter by cutting the front, did a little sanding, and I spray painted it black.

The guns actually ready, just needs a shock pump.
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Posted: Fri Jul 27, 2012 9:44 am
by jackssmirkingrevenge
Looking good :)

Any chance of a video of it firing?

I'm curious as to how fast the ball valve opens.
just needs a shock pump
Once you do that, 400 psi is a must ;)

Posted: Sat Jul 28, 2012 1:31 am
by josephlys
Thanks, I'm using elastic bands so it's easy to control how fast the valve opens by making the bands more powerful or less powerful. yeah high pressure is a must :wink:

Posted: Sat Jul 28, 2012 3:42 am
by jackssmirkingrevenge
Needs a proper sight, have a look here for inspiration: http://www.spudfiles.com/forums/oak-gun ... 17674.html

Posted: Sat Jul 28, 2012 11:53 am
by al-xg
I'm curious as to how fast the ball valve opens.
With light projectiles like that, it is very likely they are leaving the barrel before the valve is fully open.
I recorded this last summer. The pressure is quite low, but the projectile is very light. (and that YouTube music is very shitty...)
[youtube][/youtube]
I've since rebuilt it to have a much higher initial tension, which also serves as a brake just at then end to prevent the ballvalve handle from distorting as it hits the stop.

I've done shots at just over 1000psi with that airgun.