hop-ups for tennis balls

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FishBoy
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Would a hop-up (machine screw @ end of barrel) work on a somewhat large tennis ball gun? Or would it just end up snagging fuzzies?
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MrCrowley
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I don't think a screw would work, like you said it would probably snag the tennis ball. I'm not sure if a strip of rubber would work either...unless it was a small flap at the top of the barrel.

So the rubber flap wouldn't be inside the barrel, but block the exit, so as the ball is fired out it would touch the flap, and if the flap is strong enough, force the ball to spin backwards.
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I think, that perhaps a machine screw, depending on length and thread size, COULD potentially work as a hop up system, but unless it was mounted perfectly parrellel to the barrel, it would mess up your accuracy really badly, i would imagine it could throw the tennis ball to the ground, or possibly give it such a sharp grab that it would just rip the bolt off or tear the ball.


My guess would be that at high velocities, a machine screw of a couple inches, would only make contact with the ball for a fraction of a millisecond, and so likely would just screw with the ball, not give it a good backspin.
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jook13
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A small screw at the end of a barrell works great for golf balls. I think it would work good for a tennis ball as well. Just make sure it only sticks into the barrel about 1/8 an inch or so. I would try it, just to see.
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I'd like to try and get 2 hypodermic needles 1 to bleed the air out and the other to inject water into the tennis ball. Or fill it with gelatin, freeze it maybe????
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jook13
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A concrete filled tennis ball would rock!
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it would rock, but it would also pretty much be a rock :D
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But a filled and froozen one would explode on impact! :twisted:
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SP00K wrote:*looks around*backs away*
You guys are stupid.
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Now why would you say a thing like that?
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john bunsenburner
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heck there is alot of tension in the air right now I am afraid that if you filled a tennis ball with water and then froze it the flexible rubber inside would just expand and would either burst the barrel or not fit into it...Gelatin would be cool, especially if you put some kind of slit into the ball and have gelatine spray everywhere on impact! Color it red for some more effect! Concrete...I think there are better ways to make rocks, and i doubt you could get a decent velocity with a ROCK...
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You need to leave a little air space for the ice to expand. Put the hole the needle leaves straight up so only the air will escape.
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