A Drilling is a three-barrel combination gun (two shotgun barrels and a rifle barrel, vice versa, or three shotgun barrels). Most Drillings have two triggers (a very few have three triggers). The front trigger usually fires the right shotgun barrel, and the rear fires the left shotgun barrel. The rifle barrel is most often fired with the front trigger when it is selected. Most selectors are on top of the grip, but quite a few other designs can be found.
It is very important that owners familiarize themselves with a Drilling before shooting it.
The author would like to express his thanks to the German Gun Collectors Association, including members Dietrich Apel, Dick Hummel, Steve Meyer, and Hal Hamilton for helping to compile the following information on Drillings.
Most well-made Drillings in above-average condition are surprisingly accurate when using the rifle barrel(s), because of the stiffness gained with three barrels fixed together.