Popcorn Salt Question

So I bought some popcorn salt so I can have a finer salt to use for the sugar cookies.With the regular table salt I was using, I could always taste grains of salt in the cookies even when I mixed it in with the sugar and butter instead of with the flour. Like the grains are too big to get mixed in! Would I use the same amount of popcorn salt as regular table salt in my mix? Or less popcorn salt because it's a smaller grain . . . I use 1 tsp. in my recipe or regular table salt.