The grip strap markings were applied by unit armorers with whatever die fonts they were issued or obtained. It is actually remarkable that there was any uniformity at all in individual markings across the span of thirty or more years. There were regulations dictating the size, style and placement of unit marks, but you make do with what you have to work with (and not every armorer was literate enough to understand published directives). The Weimar era marking goes all wonky, and early Nazi stuff isn't much better. I find that Imperial era stuff shows much more consistentcy, but that is just me
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