Tobin Arms manufactured seven grades of shotguns in Norwich CT and eight grades in Woodstock, Ontario, Canada from 1910 through 1916.
(Frank Major Tobin lost interest in making the guns after a large shipment of walnut was lost in shipment from Europe during WW I )
Although a "four-digit" SN range can cover nine thousand guns anywhere from #1,000 to #9999, depending upon how high/low the SN of your gun falls, you might just have an earlier example.
Is your shotgun Connecticut or Canadian marked ?
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