Here's the problem with trying to date Coggies:

41099 1906
28035 1907
40967 1908
42712 1908
42126 1909
41196 1909
44230 1911
44121 1912

The serial numbers seem not to be strictly consecutive, with lower numbers sometimes appearing on later guns. Perhaps the sequence indicates when the action was completed rather than the gun finished. The pigeon gun #28035 is apparently a totally different numerical sequence.

So...good luck!

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