I have also used a stone to smooth and polish my trigger and sear and bolt to smooth action and lower trigger pull. You don't need to worry about the trigger on the Krag much. Smooth and polish the contact points if you can take the trigger group out and lubricate it all well. The Krag shoots well enough that you'll get more accuracy out of learning to control the trigger pull (press) and hold the sight picture well. I like the M1901 sight with the ladder raised and using one of the peep holes for sighting to 300 yards better than the M1902 sight with or without the Sgt Peep sight. Some do better with the M1902 sight. Try out what you have and see what works best!

Good luck and keep us informed.