Looking into it, the shells clipping through the bolt is pretty much impossible because theres a solid piece preventing it from going anywhere until the yellow shell piece is killed. It works fine on a different computer too, so it's either the beta or somehow the simulation frequency (which is meant to be 720hz for this scene), hope this helps.
I made this a few months ago but didnt upload it, but since i havent fed the piggies in a while i thought i would fill up the slop bucket with this post. (sorry to my subs, love you piggies <3)
Absolutely not my best looking, or most reliable, but i thought it was quite fun to make.
If you have any thoughts about the scene, constructive criticism or opinions or what other type of scene you would like to see, please let me know here in the comments. Have a wonderful day!
Concept is not originally mine, i got inspired by this post: http://www.algodoo.com/algobox/details.php?id=251346 , which is also a hydraulic cannon. Many thanks!