I finally got a Reply from Glasgow Library.

Dear Dale,

Thank you for your enquiry regarding the Army & Navy Shotgun, serial no. 2181. According to the Army & Navy registers of stock and sales of guns that we hold, your gun was originally purchased by Colonel Mailland on the 8th August 1885 for £23.0.0 (our ref FRAS 309/2 p 2). The date of invoice from the manufacturer is the 19th November 1883. The bore number is recorded as 12.

Unfortunately, our records do not contain the date of manufacture itself, so we have no way of providing you with this. Apologies for any inconvenience this causes.

We have attached copies of the full entry.

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