Sounds about right but remember you won't be TOWING around an empty trailer so it'll weigh more than that once you put your personal stuff in the trailer. At a MINIMUM it should be 10% or greater and could be as heavy as 15% of the GVWR of the trailer. Weighing it is the ONLY way to know for sure what it'll weigh when loaded. For what it's worth, there are a LOT of half ton trucks that can't tow their rated weight because they hit the payload limits before reaching it. Keep in mind though, each pound of people, cargo etc. reduces your max trailer weight pound for pound.
