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centrifugal vortex bbmg
Posted: Sat Jul 15, 2006 2:06 pm
by saladtossser

you get the idea, this will use air and/or an electric motor to spin, a motor alone is too slow, compressed air is blasted into the center of the spinning thing and as it forces out in every direction, it will propel the spinning thing, also a projectile inside the barrel
Posted: Sat Jul 15, 2006 2:08 pm
by Velocity
i think a dremel spinning at 30,000 RPM would be fast enough
Posted: Sat Jul 15, 2006 2:18 pm
by huse_spud
how would it be reloaded? (and yes i know its just a concept but.. you know)
would the motor have to stop or could this be made into a semi auto tyoe?
Posted: Sat Jul 15, 2006 2:59 pm
by saladtossser
bbs would come in from a hole at the bottom, like a original vortex gun
30000 rpm would give 130 fps, without any air and not counting any resistance of any kind.
Posted: Sat Jul 15, 2006 3:11 pm
by CS
How did you formulate such a number? The velocity would depend on the diamter of the wheel.
Posted: Sat Jul 15, 2006 8:30 pm
by saladtossser
exactly... i bet any average joe who went to grade 7 math can figure this out
Posted: Sat Jul 15, 2006 11:20 pm
by CS
No Shit! You never gave a diameter on the wheel. You were only discussing it in theory. Just cause you got everything worked out in your mind doesnt mean I can read it and have access to it.
Posted: Sat Jul 15, 2006 11:54 pm
by benstern
30,000 RPM that would translate to around 200-300 rounds being ejected per second. (considering that not every blade would catch a bb each time)
Also, if the bb input was pressurized with around 100 psi but the wheel was powered by dremlal would the velocity of the bbs be much higher?
It would also be more efficient if the bbs enter through the center then let gravity and centrifigal forces do the rest.
If the bbs entered the bottom a blade might be in its way, thus reducing the number of rounds per second.
Posted: Sun Jul 16, 2006 1:04 am
by SpudStuff
ohh a simple design made complicated with no benifit
Posted: Sun Jul 16, 2006 7:36 pm
by benstern
http://www.onlineconversion.com/wheel_surface_speed.htm
If the spinning thing has a diameter of 1.5 inches and is spinning at 30,000 rpm the speed of the bbs would be about 300 feet per second.
This thing has the potential to be very powerful....and loud.
Posted: Sun Jul 16, 2006 10:03 pm
by huse_spud
SpudStuff wrote:ohh a simple design made complicated with no benifit
i think the benifit would be a more continuous and more predictable stream of bb's.
i've never made a bbmg myself but ive seen video.
Posted: Mon Jul 17, 2006 2:39 am
by chosen_way
im probably wrong but anyway, wouldnt the blades spinning creat enough air so that would eleminate the air compressor all together? and also instead of everyone arguing over the design why doesnt one of use try it, i no i would if i had the money right now. most of the simplest ideas work the best

Posted: Mon Jul 17, 2006 2:59 am
by carlbelcher
most of the simplest ideas work the best
This far from the simplest BBMG design. The simplest BBMG is a cloud type BBMG that can be made with as little as 3-5 non-moving pieces.
wouldnt the blades spinning creat enough air so that would eleminate the air compressor all together?
No, I think you might be missing the point. The idea of using an air flow is to feed bbs to the spinning wheel and also to perhaps speed up the wheel. The air flow created by the wheel would have a somewhat opposite effect, it would push the bbs away.
Posted: Mon Jul 17, 2006 1:49 pm
by benstern
The air flow created by the wheel would have a somewhat opposite effect, it would push the bbs away.
Not if the bbs were feed through a hole in the center. There would be a vortex created in the middle by the blades. Bbs spinning in a vortex would move towards the outside of the vortex (the blades) due to centrifugal force. Then those spinning blades would then catch the bbs and expel them out the barrel.
I think this has already been invented. It is called a centrifugal gun.
http://www.newscientist.com/article.ns?id=dn7365
http://www.geocities.com/pest3125/pest/techinfo.htm
<img src="
http://www.geocities.com/pest3125/pest/techinfo1.jpg">
http://defensereview.com/dad/dread.mov
Posted: Mon Jul 17, 2006 7:48 pm
by The Haymaker
I very much doubt that the airflow created by the spinning wheel would be greater than the incoming air supply. If that was the case, I think that air compressors would be much cheaper.
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