The advantage of an inline vortex is that it allows the benefits of a vortex type BBMG (more reliable feed, more powerful) without the ugly tee. In other words, an inline vortex has the more appealing appearance of a cloud type combined with the higher reliability of the vortex feed.

As you can see, I made two different BBMGs, one in .177 caliber and the other in 6mm. The .177 (your standard copper BB) is made from standard 2" PVC fittings (1 female adaptor and 1 plug), 1/4" brake line, 1/2" PVC (barrel shroud), and the vortex is made from 1/2" PVC sheet. A diagram of the vortex is shown below.

While the .177 caliber model is not as attractive as the 6mm, that could be improved by using smaller diameter fittings for the BB reservoir (as usual, I used the 2" fittings because thats just what I had lying around). If I were to make one from scratch, I'd use 1" or perhaps 1.25" fittings instead.

The 6mm (airsoft) BBMG is made from 2" sch40 pipe and 2" PVC rod ordered from McMaster-Carr. It is by far the most fun BBMG I've made, and shoots about 30-40 BBs a second completely across my yard at 100 psi. The operational range is much better than a cloud gun, and will shoot at pressures ranging from 100+ psi all the way to 12 psi. Of course, once it gets below 20psi it'll barely shoot 15 feet.
The vortex is cut out of the rod directly, and the diameter of the vortex hole is 1". The air control valve should be attached to the 1/8" connection sticking out of the bottom.

The 6mm (airsoft) BBMG is actually not finished: it shoots, but it is intended to be the internals to a larger gun. I'm in the process of making an M2 .50 caliber (or perhaps a 1919A4) replica gun from PVC sheet to be used in airsoft skirmishes, mounted on top of a tank. I've spoken to several people about how desireable something like this would be, and I've received good feedback. Then again, I've got to do some chrony work to make this safe for use on an airsoft field. It will be ready by summer, that is certain.

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