As to your big old one, it is a Mouser also, but for BIG mice: 43"-calibre, to be sure. EXCELLENT Zombie gun!
The "JG 71/84" is what it is: INFANTERIEGEWEHR 71/84. The old German Gothic letter "I" looked like "J". Infantry Rifle Model 1871 with 1884 alterations (the Magazine and Cutoff.)
It was made at the Konigliches Gewehrsfactorie Spandau, just outside of Berlin at that tme: the Royal Rifle Factory at Spandau. It was built in 1887 and issued immediately.
The "Crown F.W." is the Royal Signet and descends from King Friedrich Wilhelm III. Your rifle was made during the reign of Kaiser Wilhelm I, who died very early in 1888 and was followed, for a mere 99 days, by Kaiser Frederick II, who was followed in turn by Kaiser Wilhelm II, the "Kaiser Bill" of Great War fame. Whoever held the sovereignty of Prussia also was the German Emperor (note carefully: NOT "Emperor of the Germans" but "German Emperor": there was a lot of local independence before 1933. On the coins, this was written "Deutscher Kaiser, Konig von Preussen", just to keep things straight. But your rifle was built in the last days of the reign of the FIRST modern German Emperor, the man who marched his Army through PARIS following the Franco-Prussian War. The French never forgave him for this, even though French Armies marching through OTHER folks' capital cities was perfectly allright, just so long as you had a Corsican General to blame it all on when it all fell apart.
Calibre is 11.15x60R, which was made in Canada until 1968 as the .43 Mauser. It uses the classic Mauser "A-base" case design with 77 grains of Black or 29 grains of SR-4759 and a hollowbase .433" bullet weighing 386 grains. GROOVE diameter is .446", so don't go over that figure. It will stop just about anything short of a light Tank and was/is one of the truly GREAT rounds for Moose in bush.
Barrel length is supposed to be 31.5 inches, so you can judge the Extent of Bubbafication from there.
They are a LOT of fun and, if you lay in some ammo and a set of dies and a mould, one will fill the freezer for another 125 years. These are EXTREMELY solid rifles.
Nice toy!
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