so heres my valve. notice the nut that comes with the valve.
link: http://i203.photobucket.com/albums/aa95 ... G_0438.jpg
Tactical Sniper Rifle
- Jumpin Jehosaphat
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The giant chamber is relatively useless. My C:B is 18:1, few people see the need to go past 4:1. I made the chamber huge because I think it looks cool. It makes the gun very loud while firing. I have nothing to back this up, but I personally feel it adds a bit of follow through that helps when you are using multiple projectiles.simoaka wrote:the method u have just shown us i think is excellant ill be making one but i dont under stand why you need a airchamber so big iv seen so many other forums and there small but looks great other wise, please put a vid it look interesting and i would love to see the damage that thing could do
I want to post a video, but it's hard to find somewhere open enough that I can use damaging projectiles, and where I will have access to an air compressor. I've also been busy working on a big shoulder fired tennis ball combustion cannon. Pneumatics are more powerful, but I can take my combustion cannon anywhere.
Edit: @ spudyeti, that picture is hard to see because it is out of focus, but that doesn't look like a normal schrader valve. I'm not sure what that is, but if you can figure a way to mount it to your cannon and fill it, you should have no problems.
- spud yeti
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Yeah, I also like the massive chamber look.
Sorry about the photo, I was trying to hold the nut and take the photo in the dark at the same time.
As I said in previous posts, its not a schrader, youre right, itsa kenda valve. It does work very well, so if you see them for cheap, get some!
Can wait to see the tb shooter!
Sorry about the photo, I was trying to hold the nut and take the photo in the dark at the same time.
As I said in previous posts, its not a schrader, youre right, itsa kenda valve. It does work very well, so if you see them for cheap, get some!
Can wait to see the tb shooter!

really good quote/phrase here
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my fave ammo atm is lots of small coins all at once.
ok congrats, my fave is used condomssupa_midget wrote:my fave ammo atm is lots of small coins all at once.

cant believe i haven't seen this gun yet, great job mate especially on the breech, great stuff.
peace
~chaos
- Modderxtrordanare
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chaos wrote:supa_midget wrote:my fave ammo atm is lots of small coins all at once.
ok congrats, my fave is used condoms![]()
Kids keep starting younger and younger...
But, I really like the gun JJ. Personally, I would have made the chamber smaller, so it was less unwieldily. I'd still oversize it for the noise, but I'd want a lighter gun in my opinion.
Spudding since '05. Proud waster of plumbing and plumbing accessories.
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- sniperjosh
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lol nice gun, not sure about ur barrel setup tho - bowed downards alot because of muzzel fitting's weight
. 18:1 ???? reminds me of my first ever pneumo many years ago lol. GW

- Jumpin Jehosaphat
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The barrel setup is good enough for me as it is. I may end up making a new inner barrel out of Sch 80 PVC if I ever get bored enough, the muzzle brake doesn't cause it to bow, it's just not a perfectly straight piece of PVC.

- Jumpin Jehosaphat
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You should be able to work it out from the link Gepard posted.
Here is something to consider though. In the pictures shown at that link, you will see that I epoxy'd a nut into place... bad idea, it came out a few weeks later. I recommend you drill a hole right into the barrel where you intend to attach the barrel, use a thread tap or force thread the bolt in, use Teflon tape to get a good hold. If you were wondering about the bolt itself, it is the main part of one of those quick disconnect bicycle axles. I used a Tee nut, and two regular nuts to space the bolt so it doesn't go in to the barrel at all when it is screwed all the way in.
As for the bolt action components its just a 1" SCH 40 outer barrel, a 1/2" inner barrel, there are O rings to form a seal. I recommend using a lathe for the O ring notches, but I just used a file. You also need to consider whether your projectile may be falling into the outer barrel while loading then crashing into the inner barrel while firing, I chipped a notch in the action part of a barrel when I used a hard projectile. This bolt design is very ergonomic, but you have to be careful about how you space everything, it's a little tough to build. Just make sure everything lines up right if you try to build this.
Here is something to consider though. In the pictures shown at that link, you will see that I epoxy'd a nut into place... bad idea, it came out a few weeks later. I recommend you drill a hole right into the barrel where you intend to attach the barrel, use a thread tap or force thread the bolt in, use Teflon tape to get a good hold. If you were wondering about the bolt itself, it is the main part of one of those quick disconnect bicycle axles. I used a Tee nut, and two regular nuts to space the bolt so it doesn't go in to the barrel at all when it is screwed all the way in.
As for the bolt action components its just a 1" SCH 40 outer barrel, a 1/2" inner barrel, there are O rings to form a seal. I recommend using a lathe for the O ring notches, but I just used a file. You also need to consider whether your projectile may be falling into the outer barrel while loading then crashing into the inner barrel while firing, I chipped a notch in the action part of a barrel when I used a hard projectile. This bolt design is very ergonomic, but you have to be careful about how you space everything, it's a little tough to build. Just make sure everything lines up right if you try to build this.

- Jumpin Jehosaphat
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I knew that link seemed vaguely familiar 


Would it be possible to file grooves inside the 1/2 in. for o-rings so if I shoot marbles they wont role out the barrel or into the valve?
And if you do thread a bolt into the barrel, wouldn't that get in the way of the projectile and jam the barrel?
And if you do thread a bolt into the barrel, wouldn't that get in the way of the projectile and jam the barrel?