I agree with John. There are original Prussian Dalys with features that differ from the strict catalog specs. For example, I recently inspected a fairly minty 1928 vintage Daly model 185 with extractors when the SD&G period catalog only listed ejector guns (with no option for extractors.) Someone wanted an extractor gun apparently and got it!
I think the Daly database information bears out that while many/most Prussian Dalys were made to catalog "spec" if a customer wanted a particular feature, he could get it.
Ken
