[Steven Smith]

If I understand the drawing correctly, you would essentially have an outer tube to contain both a pneumatic cylinder and a firing pin. The firing pin is mounted to both the end of the pneumatic cylinder, and a bolt that travels in a slotted groove in the outer cylinder. The pneumatic cylinder compressed, extending the latex, and then is "triggered" by allowing the pneumatic cylinder to extend again (possibly driving it back into the firing pin, but with the assist of the latex tubing). This essentially looks like a pinball launcher to me.


As noted before, two issues you may struggle with are:
-Insufficient speed on your ramming arm, as larger cylinders can often move more slowly
- Too much speed on a relatively small ramming head, which at best will lead to lower accuracy, or at worst could damage the ball.

I'd mock up something simple and see where it gets you (prototype). If you like the idea of the pinball tube, I think you may get more "oomph" from actuating it from the outside, with a mechanism that can run the bolt connected to the latex tubing backwards until it reaches a breaking point... slip off to allow the shot, then catch it back at the starting point.

I do think you would be wise to consider a few other designs that might be simpler (backup plan), but it might still be worth prototyping your original design to see what comes of it.

Steven