the M41 "prickskytte" ammo, used in their sniper rifles, used a 143 grain bullet (I pulled some of this stuff down and weighed bullets and charges)...
...and the powder charge was 46.3 grains of what was called NC1220. Fortunately, we have the same formula, now called "Reloder 22"... no kidding, that's it.
Using Sierra 142 grain Matchkings and 46.3 grains of RL22 I've shot some fantastic groups with Swedes (M96's mostly) over the years. I used Norma brass, and even Winchester and Remington with good results.
Here's a copy of an old letter from Alliant that may be of interest...
With 139's or 140's probably go with 46.5 grains of RL22... work up, of course...
the M96's are the most accurate military rifles ever built--beyond any reasonable doubt...
Dan