Your rifle
I do believe your m96 may be a Husqvarna rifle produced in the early 1940s. As you have not given the barrel length, it could be a m38 Short Rifle (65,588 made)or the m96 long rifle (18,000 made). Since your rifle has been drilled for a diopter rear sight, it is about 95% certain that it is a M\m96 long rifle. Husqvarna made these between 1942 and 1945. Your rear sight is a Husqvarna rear sight base designed to accept a dial type rear sight.
These 18,000 rifles were made for the FSR, the Swedish Volunteer Shooting Association, but to Government military standards. They were sold privately to FSR Members and other shooters, with the provision that they could be bought back by the Government in case of emergency (WW2 was on at the time.) Also, another provision was that the rifle could be altered SLIGHTLY for target shooting, as long as it did not significantly HARM the rifle. The drilling of two holes in the receiver was considered acceptable, provided the work was done by a FSR approved Gunsmith.
There were several Diopter sights available, but mounting hole spacing differed. You will have to accurately measure the spacing. If you look at the rear of the base of the rear sight, between the ears, it may have the initials SS on it if it is Husqvarna 1943 or 44 production. Common diopter rear sights were the Elit, Soderin, Pramm, Faldt or Helqvist. With that hole spacing it will NOT be the GF, Lyman, Hooka, or Busk.
PM me with the serial number, the name on the receiver, serial number, and any initials in front of the serial number (in case of a converted m96).
Of the 18,000 m/96 long rifles that Husqvarna made, 6,000 had the regular m/96 sight, and 12,000 had the "SM sikte AGJ ram" dial rear sight that adjusted from 100 to 750 meters. The AGJ (A.G. Johannsons Metalfabrik) sight was also mounted on the m38 short rifle. There are other F-ram sights that will fit, but the Vasteras rear sight INSERT was designed to mount on a standard military rear sight. These sights are available on E-Bay, or other places.
Husqvarna also did some work on the m96 rifles, converting them to m38 short rifle standards. The rear sight bases were changed on most of these rifles to the Husqvarna type rear sight mounting base. Rifles also went back to work shops for rebarreling, upgrading, or modifications. There should be stamps in the wood under the wrist of the rifle grip behind the trigger guard if the stock is original.
Also, if the rifle is in original condition, you might think twice before making a Sporter out of it, or modifying it. While not generally recognized in Canada, the FSR rifles are getting a premium in other places. These were the more accurate rifles, and not as many of them were used. If you go to Trade-ex website, and click on the "links" for the information section, go to "the House of Karlina." There is a section on the FSR rifles there.
A picture of the whole rifle would also help.
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