Dan don't you have to add 20 pounds to those weights to account for the human aspect. Everyone of them weighs more in the telling of the story. LOL. It's like fish.
But seriously I find the easiest way for me to do it is I just heft them onto my shoulder and stand on the scale. A little simple math and I have a very accurate weight. They generally fall into the 200 to 300pound zone. Well before the math anyway...