Got some photos of the most unusual double rifle I've seen yet. Made by Robert Schrader in Goettingen, 1854 – 1935 or, as most of his guns, for him by the former v.Dreyse factory, since 1901 Rheinmetall branch in Soemmerda.
The rifle is based on Schrader's trunnion breech action, his DRPatents of 1901 # 137824 and # 165257. As the trunnions are almost at the same level as the barrel axis, there is very little tendency of the hinge to open on firing. On the other hand this makes a very wide action. The left wall of the action is hand detachable from it's curved dovetails to allow the gun to be disassembled.
The triggerplate lockwork was invented by Schrader too, patented by DRPs # 89537of 1896 and # 100924 of 1898. It is a spring cocking lockwork. It's function resembles the famous Beesley-Purdey sidelock somehow. Each lock has a V-shaped mainspring, both arms engaging the hammer. One arm pushes the hammer forwards, while the stronger arm pushes the hammer back to the full-cock position. So the hammer is always at full cock, but can not swing forward unless the stronger arm of the mainspring is cammed out of engagement. In Schrader's lockwork the third "trigger" below the triggerguard serves three functions: In the middle, "neutral" position, a shown in the photos, it keeps the gun shut with the cam out of engagement with the mainspring, "Safe". Pushed forward, it is the opening lever pulling the underbolt out of engagement. Pulled back against the pistol grip, an internal cam disengages the stronger mainspring arm from the hammer, compresses the mainspring further and so sets the gun on "fire". Pushing it forward again to the middle position sets the locks on "safe" again, decompressing the mainsprings . Both triggers on this dr may be set. The rifle has pre-1912 Suhl Nitro proofmarks.
But the most unusual feature of this rifle is the chambering. The right barrel is chambered for the old blackpowder 11.15x65R LK aka "11 mm Drillingspatrone lang". This cartridge was cataloged with a "nitro for black" load, a 17.5 g = 270 gr Copper jacket, Tesco type bullet in front of 3 g = 46 gr R5 smokeless powder. But this barrel is proofed for a "Full Nitro Express load", most likely a Schrader proprietary load, of 3.6 g = 56 gr smokeless and a STEEL jacketed bullet, most likely the 21 g = 324 gr one as used then in the 11.2x60 Schueler.
The left barrel is in .600 NE , proofed for a 7.5 g = 116 gr charge of smokeless powder and a steel jacketed bullet!
The rifle was apparently built to order for use in Africa. The right, first barrel with Schrader's NE load would probably handle any game with a well placed shot, but using cheaper and lighter ammo without excessive recoil. If anything went wrong, you had the .600 in the second, left barrel as a charge stopper, just in case. The murderous recoil then probably did not matter much, as there was no third follow up shot anyhow.
Any comments or better ideas about the gun and it's purpose?