Identifying a combo gun

[Harm]

O.K.,
Can anyone help me with the maker, date of manufacture and caliber of the rifle on this combo gun? The lower barrel appears to be a 28 ga. The gun probably doesn't weigh 5lbs as it is that light.
Thanks, HarmP4290007.jpgP4290017.jpgP4290018.jpgP4290021.jpg

[Axel E]

Your gun was first proofed post-1911 in Zella-Mehlis, "Nitro" in script. The rifle barrel proofmarks are quite confusing, as the caliber was changed by reboring, lining or so. At least, it was reproofed (crown/R) in 635 = June 1935 for the 6.5x27R cartridge, 6.3mm bore diameter, 5.3 gramm steel jacketed bullet. Originally it was probably a 5.6x36R Vierling aka .22 Winchester CF. 54 may not stand for a case length, but may be a Z-M proofhouse ledger number. At the moment I can not identify the other marks. Additional photos of the action area may help to further identify it.

[Harm]

Thank you very much for your input, you are a wealth of information as I have read your posts in the past with other members. It is a very light gun, almost a youth size so 22 cal would make sense. I will try for some better photo's and upload. Thanks again. Harm