If you shoot an over & under, you owe a debt to this double-barrel shotgun. It’s the first O/U built by Boss & Co. Completed in 1909, it was a turning point in shotgun design and one of the reasons O/Us are so popular today.
Shotguns with stacked barrels have been around since firearms were created. While they were never as popular as side-by-sides, lots of makers built right through the flintlock and percussion era. But once breechloading center fires took over around 1870s, stacking barrels presented a problem.
To be loaded, most breechloader need to pivot and open. This means they need a hinge. On a side-by-side, this hinge is created by a section of the front lump called the hook and a corresponding piece in the action called the cross or hinge pin.
When you use the same set up on an O/U, you increase the depth of the barrels and the action. The result is a big, bulky gun that lacks the trim, svelte proportions of a side by side. But when John Robertson’s O/U came along, he changed all that.
Robertson was the huge brain behind some of the most influential shotgun innovations ever created. Along with Henry Holland he created the Holland & Holland Royal shotguns. Later he came up with the Boss-patent ejectors and the Boss-patent single trigger. By the time he came out with this O/U, he had already taken over Boss & Co. and turned their shotguns into the finest doubles in the world.
Robertson’s over-and-under patent borrowed a simple idea from artillery technology. They’re called trunions, and they move the barrels pivot point from underneath the tubes to the sides. This solved the problem of lumps on the bottoms of the barrels and made the Robertson’s O/U almost as trim as a side by side.
Today, O/Us dominate the market for new doubles. Many of these guns, including all Italian O/Us, are made on designs influenced John Robertson Boss patent. His idea flipped the shotguns barrels, and shotgun shooting, on it’s side. The gun making world has been different ever since.