The Finn M28-30 and M39 rifles have a simple modification to the trigger that adds two pins crosswise thru the top of the sear hole in the trigger; it allows two bearing surfaces, one as takeup the next as the stop before break.

I had a few and added them to some rifles, they are the best and simplist way to improve a M/N trigger IMO. Adding a slight angle to the sear will make a perfect trigger release.

I also learned how to make a positive double pull on a standard 91 and 91/30. Briefly, it is done by filing and polishing two angled surfaces on the sear nose. You must make the surface highly smooth and polished and also the angle cannot be so great as to prevent trigger reset on a half-pulled trigger.

It can be done, and I modified a number using this method. As such, the trigger has a first stage, then reaches a stop, then breaks. It feels different than a 98 Mauser, but can be done so as to give an even smoother trigger and release. It takes a lot of time and trial and error.

Great thread.