Sight adjustment

[hayhugh]

I have a 1914 Erfurt artillery with the sight adjustment screws really tight. I have been soaking the barrel/receiver in KROIL over night and have just put it back in a zip-lock bag for further soaking. I do have the proper tool for the adjusting. Tried to move the screws and the front screw does turn maybe I/8th of a turn but no more. The rear screw does not turn at all. The ramp does move which it did not before the soaking. Do not want to apply too much pressure but how much is too much? How far does the front blade move when in proper order. Will the blade move all the way out of the ramp when in proper order. Can I take the rear screw all the way out or will it only come out when the assembly is disassembled. Any help will be greatly appreciated as usual. Hugh

Still looking for Erfurt Locking bolt #98