No thumbhole, my HW97 doesn't like my thumb to be across the grip. I place it along the right side of the stock pointing forward. The stock on the 97 has a slightly higher comb for shooting with a scope. The 77 has iron sights, so it depends on your plans for optics.
If you're going to scope it, then the 97 for sure.
If you had to choose between an HW77 and HW97k which would you choose and why? Thanks!
My John in Pa. tuned Beeman HW97 .22 is 4 sale.