German markings on captured and reused Mosin Nagant rifles
The German Imperial Army captured a large quantity of Mosin Nagant rifles during WWI and reused these weapons extensively. During WWII, Wehrmacht captured a huge number of different types of Mosin as well. In both cases, the German captured Mosin received specific markings. Then, after WWII, DDR refurbished and reworked Mosin Nagant rifles of different versions and applied also markings. As result of this, German markings of different kind and eras are not impossible to find but rare and sometimes mysterious.

WWI German Imperial Army capture/property marking “Deutsches Reich” on a Mosin M1891 rifle. This is the most common and standard marking that you can find on a WWI era German captured Mosin. The marking could be found on the stock, like the one above including the eagle, or on the receiver, without the eagle.

Another feature of WW1 German Imperial Army captured Mosin was the renumbering of replaced bolt to match the barrel. The Finnish Civil Guard was also numbering the bolts in the same way/area but stamping the number of the District using the weapon (usually adding also an S). In the case above, that bolt belongs to a German WWI captured rifle, then in use with the Finnish Civil Guard. However the number added on the bolt is not the District number but the one matching the barrel, so a German rework.
Markings on German modification to Mosin Nagant

In the above picture we have an extremely rare German bayonet adapter for the Mosin Nagant M1891 rifles. This modification is usually marked with a crown over a gothic font letter, likely indicating the different producers. In the example above, the crown is over something like an E, that in reality should be a capital S in gothic font, already present in the books as a mark associated to these adapters. I am currently investigating markings and the history about the producers of this kind of adapters. More info and detailed pictures will follow.