For those who know anything about firearms, the double rifle has always elicited awe and respect. It reminds of the early days of hunting dangerous game in India and Africa; when men pitted their hunting prowess against the most dangerous game on the “dark continent. It elicits respect due to the fine workmanship bestowed on double rifles as well as the technology involved to make the rifle into a highly efficient firearm.
Prior to the invention of smokeless powder, semi-automatic rifles or even bolt action rifles, it was the hunter armed with a single shot rifle and cartridges loaded with black powder. What was needed was a large and thus powerful cartridge in order to bring down an elephant or charging lion Sig Sauer P226 with the one shot at the hunter´s disposal. If this shot failed, then there would be one less hunter on the planet!! Enter the double rifle. If still fired a large diameter projectile with black powder, but it had two barrels if the first shot should fail. These rifles were made in large calibers such as the 12 bore (12 gauge) so that the black powder propellant could deliver maximum shock to the target. Some of the these double rifles were designed into what is called a paradox double rifle. The first part of the barrel was smooth bore and toward the end of the barrel it was rifled to give the projectile a spin and thus give stabilization through its flight.
As the gun smithing art progressed, calibers such as the 577, 577/450, 450, 470 and eventually the 600 nitro express were placed on the market with the double rifles chambered for these cartridges. At first some of the these cartridges use black powder as the propellant but later the cartridges were loaded with smokeless powder and were dubbed nitro express rounds. The smokeless cartridges had several advantages: first when the cartridge was fired there was no large cloud of smoke to give away the hunters position and second they had a much higher chamber pressure and thus more foot pounds of deliverable energy when an animal was hit. I might add that collects in the bore of a rifle fired with black powder can produce a caustic mix that can pit the barrels. Remember, black powder has a key ingredient, sulfur which can form sulfuric acid when mixed with water.
Witch these large powerful cartridges, there was a great deal of recoil and which was transmitted to the hunter´s shoulder. These double rifles were made heavy to decrease this heavy recoil generated by the powerful cartridge and could weight in the 15 to 25 pound range. This rifle would be a heavy load for a hunter of middle age or order to carry through the tropical heat of Africa or India so gun bears were used to carry these heavy rifles. When game was spotted, the loaded rifle was handed to the hunter for the shot. After the shot was fired, the rifle was handed back to the bearer.
Normally the double rifle cartridges had a tapered case with a rim at the base to facilitate extraction. In modern times some double rifles were manufactured with rimless cartridges, but the extraction of these rimless cases can fail with the inherent problems associated with a cartridge case stuck in the chamber.
Double rifles are made with both box locks (the least expensive) and side locks (the most expensive). The side locks cab be hand detachable and thus can be removed in the field if a spring breaks, for instance. Of course, an extra ser of side locks would have to be carried in the field and this raised the price of the rifle with hand detachable side locks.
Besides the inherent labor required to produce a fine double rifle, most of the well to do hunters of the era had the stocks and metal embellished with engraving, carving, inlays, and checkering. This could drive the price skyward, depending on the owners taste for the very best that money could buy.