On the farm, we generally raise our pigs anywhere from 250 to 300 lbs. before butchering. Some may wonder how do you know how big they are. I will admit that our butcher is in such high demand that we generally schedule our butchering date at least 6 months in advance.
Outside of observation, however, we do occasionally do some weight checks on the group of pigs. It is quite a site to see us trying to get the pigs to stay still long enough to measure them but if you can, you can get two measurements and figure out their approximate weight.
The formula is girth x girth x length all divided by 400.
Tonight we measure one of the middle of the group females and collected the following measurements:
48 x 48 x 42 = 96,768
We figured that the pig is approximately 242 lbs. with one month to go.