i have a red nine mauser broomhandle. relined barrel. pretty rough shape. but a surprisingly good shooter. at first it would send spent shells flying directly at my forehead. swapped out the extractor and solved that problem. the other thing that went wrong was the sear. just got old and kept slipping out of place.
found that at the big socal gun shows look for the really old dealers. every other one had a cigar box full of parts. never the specific one you are looking for. but always good to stock up. don't trust sarco. i don't know what they sold me. but they weren't mauser springs.
the insides are a rubiks cube of interlocking metal bits. i was probably the first one to do a detailed disassembly of the thing since the thirties. took hours. but there is a logic to the way it goes together.
the thing has rifle sights. graduated up to a very optimistic 800 yards. not very easy to aim like a pistol. got the shoulder stock on and it made a lot more sense. was hitting the metal plates at 100 yards easily.
not the weapon to take on a bank robbery. ultimately it's more about the cool factor and having something to tinker with than shooting. but still damn fun.
i'm not in the market for another one. but if i was buying today i'd look for a 1930 or so with the detachable mag. using the stripper clips just got tiresome.