if script.Parent.Reflectance == 0.65 then print("Reflectance") end
if i do that it wont detect anything, but only can detect if reflectance is set to 0 or 1,i need this for part of my gun system
You're encountering a floating point error.
I'm not going to do the math behind it right now but you can essentially think of this instead as a margin of error problem.
if math.abs(game.Workspace.Baseplate.Reflectance-0.65) < 0.01 then print("Reflectance") end
Here is a link to floating point error information: