Objects have different physics speeds with high threadcount

[buildthomas]

When you say “physics of casings” do you mean that the casings are unanchored and use ROBLOX physics, or are you still manually setting their CFrame every heartbeat/renderstep?

Do you have non-rendering-dependent code that you run every frame in RenderStepped instead of Heartbeat? It could help improve performance if you moved that to Heartbeat instead.

Do you have any heartbeat/renderstepped code that assumes fixed time increments instead of using the delta argument or actual passed time?

Additionally, since this seems related to performance:

@zeuxcg

Rule of thumb when posting performance issues - ALWAYS attach a profiler capture. To get it, press Ctrl+F6 to display the profiler, and pick Dump in the menu (pick number of frames you want to save data for - 32 is usually enough for continuous performance issues). It will save an HTML file to C:\Users\yourusername - you should attach that file to the post.

Finally, when posting in Bugs and Exploit Reports, please make sure to post in a (correct) subcategory, this is helpful for staff members. In this case you should post it in Bugs and Exploit Reports > Client Bugs. You can change the category of your post by editing the title.