groundhogs are out of their holes sometimes around 9-1 around my area but most of my ghog hunting happens around 6-dusk because almost all of them are active at that time of day
i would say the average sized groundhog weighs 6-7 pounds
but i have shot one or two in the 14-15 pound range
one thing i have found that worksto get them to stand up
is using a small piece of plastic bag or a piece of a skittles wrapper and pulling it tight with your finger and blowing on the edge creating a high pitched whistle this has worked when i have used it.
good luck on your ghog hunting