Raimey, I have mentioned this to you before, and now I'll do it once more. You have quite obviously expended quite some large amount of time and effort to research this material you post on a fairly regular basis. It's very interesting stuff. While it may well be already published in many scattered places, it certainly is not collected and available in one central location. I know where you are finding some of it, but not all. I wish you would consider publishing all this information on old German (and Austrian, and Prussian, etc) makers, barrel makers, and barrel markings. Even if it's some self published booklet, you would find a ready market for it, IMO. I would certainly buy a copy. I know your research continues, but won't you consider publishing your compiled information? You can credit others as is necessary, but all this data is not published to my knowledge in one central source, and it needs to be.
State that it is compiled, I know you are not looking for credit for the information, but you seem to be doing ground-breaking work of sorts. This is the kind of stuff that is absolutely invaluable to German collectors. Won't you reconsider and think about publishing all this data?