This rifle is an ordinary BSA Shirley No. 4 Mk. I built in 1943. The rifle went through Factory Thorough Repair (F.T.R.) at Fazakerley, probably post-WWII. It had later been professionally sporterized as evidenced by the barrel marked "SURREY" and four small holes in the upper surfaces of the body for mounting a civilian scope. Happily the "SURREY" marked barrel is in full military profile including the bayonet lugs, so someone put the rifle back into its "as manufactured" military configuration. I purchased it only because I was curious about the unusual serial number.

The interesting point is the serial number which is "X 0026"

BSA is known to have used single letter prefixes in front of 4 numbers in 1942 (ref. Stratton book on No. 4 & No. 5 Rifles p. 166). Then they went to the two letter prefix followed by 4 numbers e.g. AB0961 in 1943. The serial number "X 0026" appears faintly on the body socket below the date, and then very clearly on the left side of the body and on the bolt handle. Because of the socket serial number location, it appears that this serial number has been with this rifle since 1943.

Note that BSA Shirley used the "X" prefix letter again by itself in 1945, but in this case is was followed by a number "3" and then four more numbers (e.g. X30223). This was at the very end of their production.

So the questions are:
1. "Has anyone seen any other No. 4 Mk. I with an "X" prefix letter followed by only 4 numbers?
2. If so what was the serial number and year? 1942? 1943?
3. Would you agree that rifle X 0026 was at the very end of the single letter prefix run before BSA changed to the two letter prefix? I am thinking that it was likely made very early in 1943.
4. Has anyone seen a BSA one with a "higher" letter i.e. "Y" or "Z" prefix followed by 4 numbers?

Thank you
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