Sounds about right. They grow at different rates so there's no way to tell for sure, but 272 grams for '10 would be considered maybe a little less than average in my experience. He looks healthy enough so why worry. All of mine are '10s, I have 3 males over 350 grams and 1 female who's a puny 105 grams....so he's right in between. My female is a picky eater though.