BB Auto

[PCGUY]

<div align="center">BB Auto

Provided By Boogieman - <a href="http://www.advancedspuds.com">www.advancedspuds.com</a>

Recently there has been a lot of interest in bb machine guns. I decided to join in the fun and made one of my own. The bb machine gun works on a few neat principals. Thanks goes to spudsonfire for posting his vortex design! The bb gun is fed air with an air compressor. At the bottom of the vortex tee, you will see a blowgun setup. This standard blowgun acts as a triggering system for the gun. Air blows up from the blowgun when triggered and into the vortex disk, in the meantime the tee is pressurizing. The combined efforts of the pressurized chamber and the vortex disk cause the bbs to shoot out at a very fast rate of fire.

It seems like a very complex concept, but it really is a simple mechanism. The bb's just get stirred around in the vortex and head out the barrel. There is a high flow air stream in the barrel and the bb's just follow the air out of the barrel. If you have trouble seeing the concept, just try to see it in a simpler way, it seems much more difficult than it actually is.
There are also "side plates" on the vortex disk. These are there to prevent jams due to the weight of the bbs. I believe that the side plates also help vortex action. Here are a few pics of the launcher:

<img src="http://www.spudfiles.com/official_pics/bbautolarge.jpg">

<img src="http://www.spudfiles.com/official_pics/ ... muzzle.jpg">

<img src="http://www.spudfiles.com/official_pics/ ... handle.jpg">

<img src="http://www.spudfiles.com/official_pics/ ... unmark.jpg">

<img src="http://www.spudfiles.com/official_pics/ ... _laser.jpg">

<img src="http://www.spudfiles.com/official_pics/ ... un_030.jpg">

<img src="http://www.spudfiles.com/official_pics/ ... gunfs2.jpg">

Construction Process

The vortex disk was cut from 1 5/8" solid PVC rod from mcmaster.com. The solid PVC rod is quite cheap, at only $5 for a foot. With a little grinding on the inside of the 1.5" female adapter, the rod is a perfect diameter for a 1.5" vortex tee. Dimensions are not crucial, honestly you can just eyeball the thing. The vortex hole is about 3/4". The other important part is the barrel. It can be made with either aluminum or stainless steel tubing from McMaster. The ID is .18" and the OD is .25". I highly recommend the stainless steel, it costs a bit more, but the aluminum stuff is pretty horrible. It works, but it is very easy to bend. Once it's bent it is impossible to straighten. You can sleeve the aluminum into another size PVC. The stainless is so much stronger it wouldn't really even need sleeved. Here are some pics of the procedure:

<img src="http://www.spudfiles.com/official_pics/ ... un_002.jpg">

<img src="http://www.spudfiles.com/official_pics/ ... un_004.jpg">

Unfinished Vortex Disk

<img src="http://www.spudfiles.com/official_pics/ ... un_008.jpg">

Finished Vortex Disk

Attaching the barrel is another aspect to consider. You can do it several ways. The easiest ways are as follows: Method 1(top) is to use 1/4" sch80 pipe over the barrel. You can thread the end of it, and tap the tee. The barrel stays in the sleeve by friction. Method 2 (bottom) would be to use a compression fitting, this is the easiest method, but would only work well with stainless barrels.

<img src="http://www.spudfiles.com/official_pics/ ... un_013.jpg">

Two methods of barrel attachment

<img src="http://www.spudfiles.com/official_pics/ ... un_015.jpg">

<img src="http://www.spudfiles.com/official_pics/ ... un_018.jpg">

Method 1 and Method 2 Barrel Attachments

<img src="http://www.spudfiles.com/official_pics/ ... edited.jpg">

This was the original layout of the gun. It has since been changed.

<img src="http://www.spudfiles.com/official_pics/ ... un_iso.jpg">

<img src="http://www.spudfiles.com/official_pics/ ... _front.jpg">

Provided By Boogieman - <a href="http://www.advancedspuds.com">www.advancedspuds.com</a></div>

[deathtodeer666]

incredible this will all go in to the ultimate bb gun im building estimated completion date: december

[Animal81182]

that cannon rocks i am defo gunna build one of these prob some time next year as i have loads of projects to finish first and the dosh is at an all time low!!!

what size bb do you use and are the metal or plastic???

Animal

[Gfro1234]

hey, i am building one that is gravity feed and has sort of a hopper on top, it uses Co2 and does not have a vortex, i have been able to shoot it but its not quite done yet, the only problem i have is getting the bbs to fall down into the stream of air, so i may use a funnel, not sure if this really has anything to do with yours, just thought i'd say that there is an alternative to the cloud/vortex way.

[alphawarrior]

Can you use a scuba tank for the air?

[cardinals08]

I could be just completely dumb, but it sounds to me like the BB's just fall down into the barrel, hit the air stream, and go. If this is the case, how do you stop the BB's from continuing into the barrel after the air stops?
Im still an newbie, so I want to find out as much as possible, so far I have only built a few mini spuds because I dont have the money or supplies to build a bigger one

[taz22]

me the same question ^^

[Private-Parts]

Can you make a list of everything you used to make it and thier diamiter? I want to go out and buy all of the matirial today so i can get started

[)DEMON(]

just go and look in spud wiki it will tell you in there

[Private-Parts]

I went there, and the only thing I saw has to do with complaining about people of today's grammer.

[)DEMON(]

oops , you go to the how to section and click on bbmg then click on the pic, my bad

[Private-Parts]

Hey thanks man I finaly understand how these work and what I need.

[rna_duelers]

i love that gun,gives me goose bumps everytime i see it.

[pneumaNINJA]

Do you know of any other places to get .18 stainless steel piping? I've looked around on the internet, and can not find a single supplier for non-commercial uses.

[jjk92]

i was wondering about how much did it cost to build this gun? thanks