SpudFiles

This is what I came up with. I added a 60" air chamber for more power. I hope this helps. For now I have to wait until the glue dries.


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I want more power out of my air cannon. I can very easily expand the air chamber. Would 3 2" x 12" air chambers be effective? I'm concerned the flow might get restricted using a 3 chamber design. I'm trying to keep the gun compact.

New air chamber design, will the flow be restricted too much???
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With my current cannon design the air chamber is not big enough to prodce the power I need to shoot a paint grenade or grape shot.
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It wont increase your power much, sorry to say. But if you feel like bilding 3 chambers, use 3 valves. Now THAT will definitely give you a power increase

It would have an adverse affect on flow but I would think that you would seen and definite increase in power...what does GGDT say about it? Enter it as a (single chamber with a equal volume of the combine three chambers)

You may do better by increasing barrel length...

what pressure have you tried firing it at? the heavier the projectile the higher the pressure you will need to use.

the reason for the crap capabilities now is that your valve has little flow in comparison to your barrel. Your barrel has 4x the flow of your valve. If you stuck another modded sprinkler valve then you should see a large increase in performance

the three chamber design would be good but you would need a way to support them or they might just snap off at the cross

If you double the chamber size instead of trying to be fancy, it should increse you power nicely, orrrrrrrr -- Build a piston valve if you want real power from a pneumatic.

I have fired it at 90psi. I removed the saftey tip on my blowgun and also removed the spring from inside the cp-100 valve. Those 2 simple things helped a LOT. It's still not powerful enough. I think a smaller bore size barrel will help. I have been doing some more research and seems that your projectile needs to form a good seal aroung the inside diameter of your barrel. I just tried shooting loose paintballs and the only thing I accomplished was making a LOT of noise. I would have more luck throwing a handfull of paint at someone....lol.

I think if I add another valve I can accomplish my goal.

Lentamentalisk wrote:the reason for the crap capabilities now is that your valve has little flow in comparison to your barrel. Your barrel has 4x the flow of your valve. If you stuck another modded sprinkler valve then you should see a large increase in performance

Lentamentalisk has it right here, your restricted flow is the issue. 2 more tanks feeding the same restriction is not going to appreciably increase your performance. Go with 1 more tank and another sprinker and mix them on the barrel side of the sprinklers. At the mix, go up to 2" connectors all the way to barrel. This will double the flow you have now.

If you go with another tank, you can also help yourself with a longer barrel.

What if I reduced the bore size of the barrel? lets say to 1"

With your current set up you should be running at regulation velocity; actually, depending on were you go, you may be shooting hot, it should do about 240 with a NERF which is 10fps faster than regulation 230fps.

How heavy is your projectile?

Your best bet for better power is a longer barrel and longer chamber; with an 18 inch chamber and 26 inch barrel you should be getting 170 yards of distance from a 5oz round.


**all figure’s from GGDT**

ImHUGEnJAPAN wrote:What if I reduced the bore size of the barrel? lets say to 1"

Then a 1" sprinkler is closer to ideal (for a sprinkler) for a 1" barrel. If you go with a 2' barrel length and keep the tank the same, you'll have roughly 2:1 c:b ratio. A 4' barrel roughly 1:1. Depending on projectile weight, both good performers.

In your config, you still have a dead space issue on your back elbows. With your short barrel, that is contributing to your low performance as well. Move the sprinkler right behind the barrel.

I got the same results from "ggdt". Actual performance differs greatly, I think the flow is being restricted too much. I think I will just expand the air chamber and see what happens. I will probably not see a big increase in power but I plan to extpand the air chamber to 50" using a "T" connector and 2 elbows. I will extend the two extra air chambers backwards towards the valve. see picture below.

Do you want your projectile to match the bore size of your barrel? Does a tight fit (but not too tight fit) help. ggdt implies that it does.

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What ever you do a longer barrel always helps.

judgment_arms wrote:What ever you do a longer barrel always helps.

Thanks, I'm trying to keep the gun as compact as possible, it's slowly growing in size....lol. I might have to scrap the whole PB idea and just make a fun cannon to play with.