Super Soaker Central

I know that the main way to make triggers is with a ball valve, which i'm planning on using for my gun i'm making.
just wondering though, what other options there are, and if anybody here prefers using something else for a trigger.
Any thoughts are good

For water guns, the ball valve is basically it. You can build pull valves similar to those used in Super Soakers, or you could use a garden hose nozzle, but the pull valves to build are difficult, and garden hose nozzles get horrible ranges. (which they are not designed for, obviously)

The pull valve takes a bit more experience to work with. If you can get seals to work well, you should be able to build a pull valve. Otherwise, I'd recommend sticking to the ball valve, which provides the best performance. (though its the most difficult to make an ergonomic trigger out of)

Yep, C-A's right. Take a look at our overview of trigger valves and do a search for "pull valve" on the forums. There are at least a few good discussions in there.

Another possibility is a piston valve. A spring loaded piston has a hole in it - when depressed, the hole lines up with the piping. Such a valve would combine the straight flow of the ball valve with faster opening, and self-closing like the pull valve.

Such valves are used in brass instruments, or you would have to make one from scratch.

I built something like what cantab described two years ago: the topic is here.

The design should work if the center piston is rubber and is well lubricated. My attempt to use a plastic-on-plastic seal leaked and spurted when the gun was fully charged; rubber should seal, eliminating this problem.