Yes, you are close. This designation is from the French AFNOR naming system, but since I cannot find a current listing, it is quite likely obsolete. The official European grade is now called 41CrAlMo7-10 (1.8509) according to EN 10085. Composition is as follows:
C = 0.38-0.45
Mn = 0.40-0.70
Si = 0.40
Cr = 1.50-1.80
Al = 0.80-1.20
Mo = 0.20-0.35
FYI, the AFNOR system works like this: the first two digits are the nominal C content, the next set of letters indicate the major alloying elements (C = Cr, A = Al, D = Mo, V = V, M = Mn, N = Ni, etc.) and the last digit is an indication of the concentration of the alloying elements (higher number = higher concentration). The new EN designation system works the same way, but uses the official chemical symbols for the elements instead of only one letter.
