Britisharmorers did not go about stamping DP on serviceable parts. "Drill Purpose" on a rifle for a drill team to twirl about is easy to envision. DP guns are useful in preventing unnecessary wear and tear on service weapons. Bayonet training, mechanical training, repeated assembly and disassembly, crew drills, in short any kind of training which DOES not involve firing the weapon. As a shooter, the value is nil.