Grips/H. Clark

I counted the lines per inch on a bunch of luger grips of all ages (pre-1945) in the mid-1990s and was surprised to find 17.5-18.5 lpi on a lot of them. The WW1 era grips are a bit finer. I should recount the lines. Did I err in measuring? What is the convention for counting the seration's beginning point?


Dave