Guns from early 1653

This gun information is from Witte de With's journal, dating from early 1653. I am always looking for specific information about weights for the different kinds of guns:

24pdr bronze      4400 lbs
18pdr iron        3600 lbs
12pdr bronze      2500 lbs
12pdr iron        2900 lbs
 6pdr bronze drake 800 lbs