It is to be found under the barrel just foreward of the receiver, and requires removal of the fore-end woodwork to view. It is possibly the diminutive size of this mark, and its usually hidden location, which has led to it being described as 'secret'.
In this instance, the code letter is 'M' for 1932-33, indicating that the rifle was manufacture, or at least proved, between July 1932 and June 1933. Post-War rifles such as the BSA Model 12/15 will not carry this mark.
It may not be immediately obvious, but careful observation may provide you with the information for which you are looking.
Such research is a major part of the joy of owning, collecting and shooting classic or historic rifles.
For the latter, dates of introduction of military arms can be located within the Government "List of Changes" (Lo Cs) as can dates of obsolescence and of modification or upgrade to later marks.
Basic information on these lines is on site from our .
The system ceased to be used during 1941, since there was practically no civilian firearm production for the next five or six years, and, with war-time production levels reaching unprecedented proportions, almost all military proofing was effected within the various manufacturing facilities by Government inspectors. However, such date codes as there are are still useful in dating the many firearms manufactured between the First and Second World Wars, including much output from the Birmingham Small Arms Company ( see also BSA Rifles), as indeed is true post 1952 for those rifles more recently falling into the classic class. These marks are also not to be confused with the crossed flags stamp of the miltary proof markings, which may carry similar letter codes identifying the country and/or place of inspection.
Anschutz target rifles fall into this category, and their system is given on the page for these rifles.Lest they were confused with other characters, I and Q were not utilised, so the date letters to 1941 were as follows 1922/23 - B; 1923/24 - C; 1924/25 - D; 1925/26 - E; 1926/27 - F; 1927/28 - G; 1928/29 - H; 1929/30 - J; 1930/31 - K; 1931/32 - L; 1932/33 - M; 1933/34 - N; 1934/35 - O; 1935/36 - P; 1936/37 - R; 1937/38 - S; 1938/39 - T; 1939/40 - U; 1940/41 - V.The alphabet was restarted several years post-war in 1950 with A, but now each letter change was made at the beginning of the year.There is therefore an undeniable possibility that year letters after 1958 may each represent dates that should be advanced one year, with "Z" falling in 1975, although this would then conflict with the 1975 commencement of the next series. Conjecture may suggest that perhaps there was even indecision at the Birmingham Proof House, and only a few rifles were stamped with an "I" in 1958 before "J" was substituted, or, a long shot, the 1957 "H" stamps wore out before the end of the year.We may never know the answer, but can meanwhile entertain ourselves dreaming up such explanations.The two markings are shown below, the International to the left, and Century to the right.From 1975 a further modification was made to the mark, as in Figure III, with another adjustment soon after to Figure IV.Many, but not all, of our pages carry date information on the various rifles illustrated or discussed, where it has been possible to be sure of data.There are a number of methods by which a rifle can be dated, or at least bracketed between certain years of manufacture.The mark was modified to that shown in Figure II, with D to the left representing 1953, and the B to the right identifying the Birmingham Proof House. Thus the year codes have hitherto been understood to be 1950 - A; 1951 - B; 1952 - C; 1953 - D; 1954 - E; 1955 - F; 1956 - G; 1957 - H; 1958 - J; and so on through to 1974 - Z; ................we also believed that Q was then used in this series for 1965.