there are several photos of spandau rifles on the internet in which you can see the type of crown and the stamped lettering used on rifles of the same time period. here some example. is it reasonable to think the factory would use a different style of crown on lugers, if they made them or reworked them? the style of the crown on the rifles does change over the years but the 1918 rifle has a most unique crown. one that not appear on the lugers from 1918?
http://www.google.com/imgres?hl=en&c...r:8,s:12,i:142
http://www.google.com/imgres?start=2...59&tx=62&ty=42
http://www.google.com/imgres?hl=en&c...67&tx=50&ty=91