Just got an HW 77. (I promise, I'm done buying HW's for a while)
its the older model. is this stock walnut or beech.
The key is the light "flake" elements seen on the lower edge of the fore end, and under the cheekpiece. These are caused by radial nutrient channels in the wood (medullary rays), which are tiny in most kinds of wood, but very prominent in oak and beech.
Also, walnut will almost always have that characteristic lovely translucent quality; beech has a surface that is completely opaque.
To the credit of HW and Dr Beeman, these guns have some of most beautiful production beech stocks ever.