Backspin

Building or modifying BB, Airsoft, and Pellet type of guns. Show off your custom designs, find tips and other discussion. Target practice only!
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singularity
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Fri Apr 06, 2007 5:17 pm

i have a vortex gun and i was wondering if i could drill a few small holes at the top of the end of the barrel to create backspin. would this work? or would it be completely useless
be sure to check out my <a href="http://www.spudfiles.com/forums/ak-styl ... 9.html">AK Styled Vortex Gun</a> and my <a href="http://www.spudfiles.com/forums/at-4-t9627.html">AT-4 Rocket</a>

upcoming projects... finalized clip fed BBMG and ball point pen sniper
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paaiyan
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Fri Apr 06, 2007 5:25 pm

I don't konw about holes, if you put some horizontal grooves it might work though.
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hi
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Fri Apr 06, 2007 5:27 pm

if you cut an inch off the top half of the barrel it would give you some, if the bb's fit tight in the barrel.
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singularity
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Fri Apr 06, 2007 5:35 pm

well the bb is 6mm and the barrel is 6.35 mm so its not all that close. does anyone by change know the actual adjustable backspin mechinism used in airsoft guns
be sure to check out my <a href="http://www.spudfiles.com/forums/ak-styl ... 9.html">AK Styled Vortex Gun</a> and my <a href="http://www.spudfiles.com/forums/at-4-t9627.html">AT-4 Rocket</a>

upcoming projects... finalized clip fed BBMG and ball point pen sniper
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paaiyan
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Fri Apr 06, 2007 5:46 pm

Why would you cut off the top half of the barrel, that would cause more contact with the bottom part of the barrel and give topspin.
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boilingleadbath
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Fri Apr 06, 2007 7:58 pm

I've had success producing spin on golfballs using a rubber patch on the top of the barrel (moved into position by a bolt).
Perhaps a small screw, without the rubber, would work for your smaller bore?
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Mr.Russ
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Fri Apr 06, 2007 9:22 pm

you could just put a really small flat blob of hotglue or epoxy, it would act as a hop-up type thing(I think thats what your after?)
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frankrede
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Fri Apr 06, 2007 10:13 pm

or get on of a broken airsoft gun with hop up.
http://www.airsoftatlanta.com/sale.htm

1.99 each
Current project: Afghanistan deployment
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subterranean
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Fri Apr 06, 2007 10:33 pm

Drilling small holes in the top of the barrel twards the end sounds like it might work. Is your theory, that the holes will let air in to put drag on the top and cause backspin? Some paintball guns have holes drilled in them, in a spiral pattern, idk, but i think it's to put spin on the ball.Do some testing with some of the pipe your using by blowing in to. Id be interested in hearing your results.
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jimmy101
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Sat Apr 07, 2007 11:37 am

For BBMG's people have cut a narrow slot perpendicular to the length of barrel a short distance before the muzle. Then use a small rubber band or O-ring around the barrel that fits into the slot as the "hop-up" mechanism.

Making the slot deeper allows the O-ring to block more of the barrel. Too challow and it doesn't do anything, too deep and it robs to much of the muzzle velocity.
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singularity
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Sat Apr 07, 2007 5:42 pm

i just bought a $8 airsoft gun online (mostly cause i wanted the ris mounts on it) but i guess i could take that the hop up system from it. i was really hopping someone knew how the adjustable ones on high end guns work, does any one have like a diagram of one? i was just at a paint bal srore the other day and saw the spiral holes in the barrel, that where i got my idea. im going to try the slot idea, seems like the simplest. i might not try anything until i get my in-line vortex running (i have a tee variant now but i don't feel like screwing around with it, its the only gun i can use in games right now
be sure to check out my <a href="http://www.spudfiles.com/forums/ak-styl ... 9.html">AK Styled Vortex Gun</a> and my <a href="http://www.spudfiles.com/forums/at-4-t9627.html">AT-4 Rocket</a>

upcoming projects... finalized clip fed BBMG and ball point pen sniper
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FiveseveN
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Sat Apr 07, 2007 6:17 pm

i was really hopping someone knew how the adjustable ones on high end guns work
AFAIK there's a rubber piece at the muzzle, like all hop-up sysems and screw adjusts how much it protrudes into the barrel. More friction creates more backspin (though friction is something we usually avoid).

I don't see how assymetric holes at the muzzle would affect the projectile significantly, especially by allowing air IN. You're creating pressure inside the barrel to push the projectile OUT, right?
iknowmy3tables
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Sat Apr 07, 2007 6:51 pm

I don't know whats the deal with having a device just at the muzzle verse the breach

but it guess if you want to make a device then use a saw and cut a spiral cut on the inside sleeve then put the sleeve back on and clean up any burrs with a drill bit and then put the sleeve back on
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