WaterWar.net

This is the best ¾” ball valve for homemade water guns I’ve found:

Van Enterprises 3/4" PRO Series- 2PC PVC Ball Valve with Stainless Steel Handle and Chromium ABS Ball [Available 3/4", 1", 1.5", 2", 3"]

https://www.amazon.com/gp/product/B082T ... 20ZL&psc=1

The valve opens with little effort and doesn't contain lead. At $13.50 pricing is decent. Has anyone found any other valves that you've found are good?

I've just tended to use 3/8 inch brass ball valves from local hardware stores. I think the answer depends on the situation. For high performance guns I would prefer 1 inch ball valves, though they are much harder to open. But for the kind of guns I've tried to design over the years (more ergonomic ones), I go for smaller valves since they open more easily. That said, threaded valves are preferable to unthreaded ones, since you can replace the handle with a custom one. That is something to keep in mind.