I won this one on Gunbroker last week.
That marking is an SYT in a circle. It was used on M91 stocks converted to M28 stocks. I believe it was an inspection mark. So It means that back half of that stock was first an m91 stock, then converted to m28 and then the back half was cut and spliced to be used on an m28/30.
I’d have it researched to see if the stock was originally two piece or was done in a repair.
M/28-30, S/N 43878, S 23809, was factory-tested for high pressure and for accuracy by K. Vuoksela at Suojeluskuntain Ase- ja Konepaja Oy (later SAKO Oy) at Riihimäki on 16 May 1936. The records indicate the stock was two-piece ("extended" in Finnish) walnut from the factory. "SYT", or Suojeluskuntain Yliesikunta, Taisteluvälineosasto ("Ordnance Department of the High Staff of the Civil Guard"), is an inspection and property marking. The rifle was inspected by Harry Mansner and another inspector on 11 July 1936 and Shipped to Turunmaa Civil Guard District on 4 August 1936.
From there it was received by Turku Civil Guard, one of the largest individual Civil Guards in Finland, on 3 June 1937, or almost a year later. The rifle was used by two Guardsmen between July 1937 and October 1939, Zachris Valmari and Veikko Mainio Salminen (b. 16 May 1915). Salminen returned the rifle to the armoury on 3 October 1939, or some days before the mobilisation of the Finnish Defence Forces. Here the records indicate the rifle was then probably passed on to reservist Toivo Armas Veriö (b. 21 September 1919, d. 11 January 2000) serving at a coastal battery at the Archipelago Sea at Utö Island on 14 December 1939.
Interesting enough, on the same very day in December 1939, Utö was attacked by two Soviet Gnevny-class destroyers Gnevny and Grozyashchy, but also several airplanes. Utö drove them off with its four 152 mm coastal guns. Veriö continued serving with the Finnish Defence Forces at various artillery batteries during the Continuation War and post-war and rose to the rank of Lieutenant Colonel by 1974. The rifle was officially transferred over to the Finnish Defence Forces on 31 March 1940, but was returned to the Civil Guard at some point in late 1940 or early 1941. It was again issued from Turku Civil Guard Armoury to Guardsman Veikko Mainio Salminen, who used it before the war on 23 March 1941. It might be that he also used it during the Continuation War, but that is to be still researched.
