The O-Prefix books record:
No.
Barrels
Action
Actioned By
Stock
Finisher
Weight
Sold To
Date (of delivery)

References to barrel description in the relevant column record material, gauge, chokes and length.
References to actions in the relevant column record details like lever, hammer or hammerless, one or two triggers, model name, etc. Among the model names present are:
A&D (Anson & Deeley)
Ovundo
Centenary
Heronshaw (first recorded in Sept 1923)
Explora
Super Magnum Explora
While most of these serial numbers are prefixed with an O, some are altered to prefix with C or B or D, or used without any prefix at all (often these numbers are used for ‘fitter-in’ barrels. That is, new barrels fitted to an older gun).

For example, No.1987 is assigned to new 12-bore, Westley Richards steel, 28” barrels choked cylinder in both, fitted into gun No.7702 on 26th September 1935 for a Capt. P. Macnamara.

An example of a gun with an 0 prefix is No. 01474, which is a 12-bore Heronshaw with 30” barrels, made to pair with No.9109, for a Stephen Cox on 30th August 1924. It is a two-trigger ejector, actioned by Ward, weighing 6lbs 12 1/2oz.
Unlike the G and T-prefix guns and rifles, the O-prefix series is widely assigned to individual customers as well as other retailers. Trade customers are recorded (like Lyon & Co. London and Manton & Co. Calcutta) but individual customers are listed at leas as often as trade customers.

Among the customers listed are the Marajah of Patiala, the Khan of Bhopal, and Sir Percy Wyndham. Renowned author and hunter J.A. Hunter owned a .470 with detachable locks, 28” barrels and a single trigger, made in 1924 with serial number 01431, built for A. Sydney Waller. Hunter acquired it secondhand in 1938.

These guns appear to have been medium quality in general. However, there are exceptions, like No. 02142, made in 1950, and noted as a ‘best quality, Scott lever, detachable lock’.

O-prefix guns and rifles appear to have been made mostly outside the Westley Richards factory by outworkers, with actioners like Phillipson listed and finishers like Cross, H&J and Harris also noted.
They may have been stocked in-house, as stock dimensions are usually listed in detail without a named stocker being noted.
Hello, I recently added a Westley Richards side by side shotgun to my collection. It’s serial number is 02001. It is a 12 gauge with 2 3/4 inch chambers and has 28 inch steel barrels. The forearm is a “beavertail” design. The stock is a straight English style. The butt is checkered. It has two triggers.
Would you be able to supply any history on this fine shotgun?
Thank you for any follow up can provide,
Sincerely,
Daniel Hill
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