Your rifle is a Swedish Mauser, model m/96, from the date of the design. Initially they were actually made by Mauser in Oberndorf, but very soon the Swedes, with their superior steel, were making it themselves at the Carl Gustav Weapons Factory in Eskilstuna.
Please read this about the disc -
The second design has two variations. Both were used after the adoption of the new cartridge in 1941 and were divided into three sections. The largest of the three sections in either pertains to the barrel at the throat of the chamber. Measurements were taken at the throat to check for erosion.
Section I in the first variation’s exterior row of numbers reads 2 through 5 and the interior row contains 9, 0, and 1. The exterior is assumed to begin 6.51 and the interior 6.48. To read these disks just replace the last digit (1 or 8 ) with the marked digit, with zero standing for 10 and 1 standing as 11. So a first variation disk marked on the 9 has a 6.49mm bore and one marked 1 is 6.51mm bore. When the barrel erosion reached 6.55mm, it was decommissioned and replaced.
The second variation is similar, but accounted for a minimum acceptable diameter of 6.46mm. The exterior row is marked 6.51 followed by 2 through 9 and the interior contains 6.4 followed by 7-9 and a 0. An arrow over a particular number substitutes for the 1. For instance, a disk with 6.51 and an arrow over the 6 would indicate a diameter of 6.56. When the diameter reached 6.59, it was replaced.
Section II contains numbers 0-3 and referred to the condition of the bore. 0 would indicate a bore with no rust, abrasions, or corrosion. 1- Minimal darkening in areas. 2- Some rust or corrosion along the borders of the lands and grooves or within the grooves themselves. 3- Rust throughout, but without sharply defined edges. 4- Significant rust with sharply defined edges or corrosion throughout. When the bore reached an evaluation of 4, it was replaced and is therefor not listed on the disk.
Section III indicated the hold over the shooter must apply to the rifle. This applied to rifles sighted for the original 94 cartridge and was meant as an adjustment when using the newer m94/41 cartridge. The disk has three markings. “Torped” meaning “spitzer” which refers to the new 140 grain count spitzer round that was in use. “Ӧverslag” meaning the “impact above.” And “Str” which was the abbreviation for “streck” or “point” and indicates how many decimeters (or 10 cm) over or under the shooter would have held at 100 meters. In 360 degrees, there are 6,300 streck, so each meant an adjustment of 1 decimeter for every 100 meters. This section was not always marked, however.
Thanks to C+R Arsenal.
The four little holes on the right side of the butt are where the metal range-table sign was attached. You can buy a replacement for this item for around $25 - 30 from a specialist supplier. Remember to fit it upside-down so that you can read it by simply looking over the stock as you hold the rifle. I have no idea what may have been on the left side as I don't see that image.
The muzzle end of the barrel has not been threaded, so this rifle has probably not been in military service, but in the ownership of a civilian shooter in the FSR, a kind of Civilian Marksmanship Programme. The use of an attached range-plate supports this theory. Beginning in 1938, this model of rifle in military service, called the m/96, would have been converted into the m/38 short rifle. It would have been shortened by about six inches of barrel, had the bolt handle turned down and the muzzle threaded, and also a different front sight, marked T [for torped - Spitzer]. The threading is to take the blank firing attachment - BFA. The blank cartridge uses a wooden bullet to make a realistic recoil, and the internal structure of the BFA shreds it on firing. The rear sight would also have been changed for another design, after conversion to the new-shape and weight of bullet [the original was a long round-nosed design] in 1941. And BTW, military men here can see that the 'streck' is actually one milliradian or MIL.
My own m/96, a rare three-digit Carl Gustav made in 1898, went into the arsenal at Carlsborg in 1938, but was not altered in any way except for a new stock and muzzle threading. It has a totally blank stock disc.
tac