DONT TAP.if you do it increases the amount. no problem anyhow no matter which way ,just do it same every time.my measure is 36 years old from thompson and still made today. it has no top on it to level the amount.like cayagug said, i use my knife to level it on top.hunting, i pre measure out 2 loads in flim canisters so i dont have to play with it in cold etc.only thing i dont like about the thompson measure is i spill some powder as top is to wide to pour down barrel. i like the ones with spout on but to cheap to buy it, ha.i use funnel at shooting range to pour powder in barrel as in hurry, i spill it.it works good with funnel.