Swedish mausers are all threaded the same from the Mauser M-94 carbine contract until the end of production , using Mauser's thread sizes . The barrel thread is .980" x 12 TPI ( threads per inch ) . This is a small ring action . Another example is the triggerguard screws , which are 1/4" - 22 TPI . You will see metric threads used on the many diopter sights & mounting screws used by the Swedes .The Lyman being the exception .
Although not ideal, replacement barrels threaded to the correct pitch and O.D. and cut with the 60-degree profile are servicable when installed in receivers cut to the 55-degree Whitworth spec. They will screw in just fine and tighten. That combination of parts has been used successfully in America since WW II. DDR
It took a little more digging than I anticipated, but here is a brand new surplus 1943 Husqvarna receiver. It has no Swedish serial number, just a very descrete one applied by the importer (GPC). Also here is a new M1894 17.7" (450mm?) Swedish military carbine barrel. Its thread pitch gaged at 12 per inch and the major diameter of the threads is 0.980". I was unable to locate my thread profile gage, but the pitch gage (@60 degrees) was not an exact match to those threads cut in the barrel shank. I believe them to be 55 degrees.
Also, FWIW, I have small-ring Adams and Bennett barrels (60 degree profile) in both 6.5 x 55mm and 7 x 57mm that fit into the small-ring Husky receiver pictured. HTH DDR
Mauser used a 55 degree Whitworth thread , .980" x 12 TPI ( this is NOT metric ) in the Swedish mausers . Twelve threads divided into one inch equals .08333" . That is your thread pitch in inches . The included angle is 55 degrees .
According to Jerry Kuhnhausen's book on Mauser Bolt Action Rifles , a US made barrel with the 60 degree threads should be rechased with a correct 55 degree die before installing in an original Mauser receiver with the .980" x 12 TPI ( 55 degree ) threads .
I have a gunsmith friend who has taken notes on nearly every gun he has worked on over a 50 yr period. Things like threads, sizes etc. He had very little info on swedes funnily enough but as he said never saw any through his shop, which I thought was a testament to thier reliability. Anyway I said i would find out for him as I thought they where metric but this has confirmed his thoughts of being imperial.
All Mauser threads (from the M67/69 prototypes, through to the WW II Kar98k, and all the ones in between made in Germany (or cloned elswhere) are fitted with 12 TPI Withworth Form (55 degree) barrel threads of two different diameters ( .980 for small shank, and 1.010 for large shank barrels) All Mausers have 1/4x22TPI Withworth "King" Screws ( main receiver screws).
This all came about because Paul Mauser, whilst working in Liege, in 1866-69, and building his first Bolt action prototypes for Norris, the Remington Agent, was using screws common to Belgian screw making equipment...which was set up in English format (Imperial leadscrew lathes)...hence the 1/4x 22 (22tpi being a "nonstandard" thread for Engineering, the common BSW being 1/4x20, and the BSF being(at that time) 1/4x25 (later x 26). Gunthreads tended to be made in "NON-Engineering" pitches, to avoid the use of common (soft) screws in gun making.
As Sir Joseph Withworth had already developed his rational standard screw thread system well before the 1860s, it was obviously the type used in Britain and the nearby Continent, which acquired its machine tools from Britain in the 1830s-60s. The US Sellars system was only presented in Philadelphia in the early 1860s, during the US Civil War...it was an Inch based system, for both fine and general Engineering, but with a thread form based on the French metric of 1792,(60 degree) via the practice of the US Springfield Armory; The Armory used French metric ( adapted to inches) since 1795, when it adopted the French Charleville Musket M1777 as the basis of the US M1795...this continued till the end of M1873(M84) Trapdoor production in the early 1890s...the Krag introduced the Sellars unification into US Gunmaking. Remington, however, used the Sellars system, and Pratt&Whitney machines from the RollingBlock onwards.
Getting back to Mauser, when he had his M71 rifle accepted by the Prussian Army, and then started making Contract versions at Oberndorf, new machinery for the Government Factories obviously came from both Britain and the US. (Loewe was still only a Sewing-machine maker, then). This set the pattern for the barrel thread and the King screws. For the smaller screws( sights, cleaning rod, bolt stops, etc, all parts which were developed after the initial M71, Metric was used for the finer threads; but for the recoil cross bolt thread (in the M98 series), the thread was also 1/4x22...as the machinery to do it was already there.
The Only "Mauser" to have totally different threads is the Siamese Type 45/46, made under Licence by Koishikawa Arsenal, in Tokyo; the barrel follows small shank dimensions, but the thread is closer to a 2mm Pitch ( 12,7 TPI); and the dimensions and threads of the King screws are also different. Japan's Armouries at the time were working with both Pure metric systems and also the original Sellars standards, introduced when the JALCO (Japanese-American Locomotive Company) was established, using US prototypes and engineering to locally produce Locomotives for the Japanese National Railways.
Thread specifications for Gunmaking combine the modern metric and imperial systems with ancient craftsman's threads, roughly unified by a series of events (the French Revolution, the establishment of national armouries, and standardisation, and a wish to "monopolise" Gun production to a limited ring of makers, and avoid " entry" to more general screw producers
(or illegal users/repairers....especially in the Colonies).
When the Mauser system was first designed, Withworth's system was the only fully rational and standardised system with wide acceptance...even though Metric had been adopted by the French in 1792, it was still a "minority" player, and there developed "French" metric, "German" metric, etc...a situation which was only fully rectified in the 1950s.
If you want to create a bunfight, start talking Gun threads.
regards, Doc AV
( Brought up Imperial, survived Metrication,(by a 10 year stint in Europe) and now work always with a combined "Inch/metric" dial caliper, and a combined 55 degree/60 degree multiple Thread & Pitch gauge...but I still refer to a large wall chart just to make sure what thread I am working with ( BSW, BSF, USC, USF, USF-SP, MA, MB or M Unified ( or even BA or Theury/Lowenherz---Instrument threads), and of course, all the "one-offs" like the Mauser threads and the Springfield Armory threads.)