I think I have read where the lighter bullets do not stabilize in the fast twist rate of the barrel.
When choosing a bullet for Swedish Mausers, pay attention to the bullet's profile. Many low drag bullets have a long nose, and a relatively short body. As far as the throat is concerned, this means they are SHORT -- the long nose does not engage the throat, and you get the same jump to the lede that you would get with a shorter bullet.I see that Midway USA has just put the Hornady 143 grain ELD-X 6.5 mm bullet on sale at 10% off, you might wish to try it.
When choosing a bullet for Swedish Mausers
I do the same with a sized case. Plus it is stable enough to use as a jig when setting up your sizing die. Once the sizing die is just barely snugged to your "loaded" round you can calculate the amount to back off. Reloading die are standardized at 14 threads per inch or 0.071" per rotation (about 0.018" for a quarter turn).What I do is take an unsized case, insert a bullet by hand (use a bit of toilet paper to keep the bullet in place if necessary) and chamber it. The bullet contacts the lede and is shoved a bit back into the case.
Then I eject the cartridge and measure OAL and back off a bit on my seating die.
I also take the bullet and twirl it in the muzzle, and subtract the distance from the nose to the twirl mark to get the throat distance. When I go to a different bullet, I use this to determine how to seat the new bullet.
That would not be a good idea. Stick to published loads, even a bit below max, and work for accuracy. The 6.5X55 is the standard moose cartridge in Scandanavia, and is more than enough for deer.What I am shooting is a 94 Swedish carbine so it looses a lot of velocity due to barrel length. I was trying to help that a bit for deer hunting.