I acquired an O/U combination gun built in Germany 1927 in 16ga and what was 8X57R. The rifle barrel has been fitted with a full length liner in what is supposed to be 5.6X50R. But it isn't marked with 5.6X50R. Attached are photos of the proofs. Of course I can't read German, so I don't understand the difference between Einstecklaub marked on the rifle barrel, and the word I'm used to seeing, which is Einstecklauf. Is this liner removable or permanently installed? I'm think the latter. Any input would be helpful.
Photos:
https://postimg.cc/gallery/XCyLX63
