We had them in the late 50's but they told us nothing. L E (Sam) Wilson made a few spinners then. I talked with Sam about the project and this is what he told me," Bob save your money." "They don't tell you a damn thing". "In fact, shoot the bad ones and throw away the good ones". "I'm sending back all my bullet spinner orders". "For a spinner to tell you anything, you have to spin the bullet at its rotational velocity and thats not going to happen". "Thats why we benchrest shooters make our own bullets". "If you have good bullet dies and uniform jacket wall thickness and know how to use them, then spin your bullets through the barrel".They had bullet spinners in the 70-80s .