Mouse.TargetFilter with string

So I am making a gun script in Roblox. I am using parts made INSIDE A SCRIPT with Instance.new() for bullet tracers because I refused to use beams. The reason I am making this post is because I want to make the bullet tracer parts undetectable to Mouse.Hit and Mouse.Target. Since I cannot select the bullet tracers as an instance because they don’t exist yet, I wanted to know if I could use a string with Mouse.TargetFilter in the way that I don’t have to use an instance value.