Abstract: A shoulder firearm, such as a sport rifle and the like, has a cheek-piece which is adjustable vertically and laterally with respect to the gunstock. Two spacer members are loosely positioned in correspondingly aligned bores or recesses in the cheek-piece and gunstock. Each spacer member has a plurality of pairs of opposed parallel surfaces and the distances between each pair of parallel surfaces are different. The spacer members may be in the form of blocks or cylindrical elements. By varying the placing of the spacer members in the recesses or bores of the cheek-piece and gunstock, the cheek-piece can be set at different heights.