BP's typically gain about 100 grams a month for the first year or so of life. If he hatched out in early March, I'd say 600-700 grams would be about normal. My consistent feeders usually hit 1000-1500 grams by a year old. They do not maintain that pace though.
Lucifer Sam, Siam cat...
Always sitting by your side,
Always by your side...
That cat's something I can't explain...