Oh...sorry...that is exactly what I meant, as stated by TbyG. What is your serial no. range? They were produced into the high 900,000s. I purchased two of the imports from China. Both had badly worn, but not pitted bores. One is pretty close to a smooth bore. But, for the sake of discussion, most of the Prussian contract did have a red 9, although you are correct that not all did, about the first 1/4 of them, and you can determine if your pistol falls into that contract from the serial number. As far as I know, the Chinese never did brand any of them with the red 9.
They were (are still) great copiers and imitators and even produced some of their own with fake Mauser markings. I just thought that without the red 9 and the overall external appearance of your specimen, that if it had a badly worn bore there would be a good chance it had spent many years in some warlord's arsenal. I'm not disparaging your pistol in any way...it has character, and every year they become more difficult to locate. Nice find.
Attachment 243546
Click to enlarge.
This is one of the Chinese imports that I purchased and reblued. I wouldn't have refinished it if it had looked as good as yours.
DG