I am trying to make FPS arms, but when I made them lerp to the player’s camera, it’s not very smooth and delayed. I have tried welding and setting the angle of the arms but I’m struggling with that too.
Any help is appreciated! 
I myself actually just recently had this problem. Some one recommended that I use a spring module to handle viewmodel movement, and so far it’s been terrific.
Link to that resource here: spring - Roblox
The idea is that you apply force to the spring object, and in a RenderStep, you update the spring each frame. Read from the spring’s current position and apply that as an offset to your viewmodel’s CFrame.
(I also assume you’re using a viewmodel for the FPS arms.)
I don’t really want to use a viewmodel for the arms because the viewmodel element decreases the quality of the object.
So you’re attempting to modify the player’s actual arms?
No, no.
I’m using a model parented to the CurrentCamera.
That’s what I meant.
Anyways, my original reply should still apply in that case.
Alright, I’ll try it out and see if it works out for me.