Comb
Also: Stock Comb
The top edge of the buttstock where the cheek rests, which sets the shooter's eye height behind the sights and anchors a repeatable cheek weld.
The comb is the upper edge of the buttstock running from the grip back toward the heel, and it is the surface the shooter’s cheek settles onto when the rifle is mounted. Its height determines where the eye sits relative to the optic, so a comb that matches the rings places the eye on the scope axis the moment the face touches down. A comb that is too low forces the shooter to float the head, breaking the consistency that accuracy depends on.
Because modern optics sit high above the bore, a fixed comb often cannot meet the required sight height, which is why many precision stock designs add an adjustable cheek riser to lift the comb. Either way the goal is the same: a comfortable, repeatable cheek weld that brings the eye to the same place on every shot.