Erfurt c/RC mark survey

[micmacman]

i just put a Erfurt Luger on layaway,a 1917 that has the C/RC marking on it as well

i have a couple Gew 88 Commission rifles that have the same proof,and a while back we had a discussion about it when i inquired about what its distinction was,and all that chimed in had it on a Erfurt Gew 88

is this a proof mark indicative to the Erfurt arsenal solely?

also what was determined the meaning of the mark (not 100% sure if correct) was that it signified a part that had a correctable flaw,that merely need some minor attention to bring up to standard,,,,,is this correct?

also what do you mean by "standard or LP"?

year -1917

serial#- 7661f

reciver right side above inspection proofs
forward part of trigger guard

i will examine more closely when i get it paid off and edit as needed