Is this Spandau 'squirrel'? it looks like a DWM one
Q1: Does Spandau proof always come with Spandau toggle link?
Q2: Gortz and Walter said "surely.... Spandau guns were caninibalized from damaged guns during a time of great stress -- the great Spring Offensive of 1918".... no further explanation in the article though.... why 1918?
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Initially, I guessed samples having 1918 on chamber.... but on second thought, that does not explain why only 1918 guns were damaged.