The rifle started as a Romanian M1892 Mannlicher made by Steyr in 1893, essentially the same action as the Dutch M95 Mannlicher. Steyr sold lots of rifles from the military production line to private parties then. The Steyr serial number is 3272.Apparently it was in stock somewhere for some time.
George Gibbs, Bristol, imported lots of Mannlicher and, later, Mannlicher-Schoenauer rifles in military configuration and sporterized them to variing degrees, both for sale under the Gibbs name and for retail by other, even "name" British gunmakers like Rigby, Purdey and Atkin. The rifle bears a telltale B-prefix Gibbs serial number B 3175 on the barrel, but no Gibbs address, as it was retailed by another. In the Gibbs serial number system the B prefix meant: "Barreled action bought in, stocked, sighted and finished by Gibbs". On cheaper grades they merely altered the straight grip Military stocks, altered, checkered and refinished them. For some more Money they completely restocked them, most often with "Prince of Wales" pistol grips. The final retailer added his own number B 1901 on the triggerguard.
Here is again a photo of my own , Steyr 1899 dated, Gibbs Mannlicher, Gibbs serial number B 3085. The barrel is inscribed: GEORGE GIBBS . BRISTOL & 35 SAVILLE ROW.LONDON.W.