Can anyone tell me what the letters “ch” on a bnz MG42 Barrel denote? Is it that it’s Chrome lined, as it definitely is? However, it has a “cr” marking near the extension piece, and I thought that “cr” was the indication on the barrel that it’s lined.....not “ch”? I also wonder if it is an indication of the year of manufacture...as you see this type of year marking for late war Steyr 98K barrels, ie., “ED” for 1944. The difference however, is that the letters used to indicate Barrel production on the late war bnz made 98K’s are capital letters...not lower case. Perhaps someone can answer this question for me?