I've had my Ruger M77 Sporter (20" barrel) since maybe 1990-91, and the first loads through it were factory, both Winchester and Remington. It was a solid, 2" shooter at 100yds.
I changed the sear and trigger spring with one from Timney, and that helped a bunch.
Next, I started using Hodgdon's Lilgun powder and the groups went to MOA, or a bit better, and then switched to small pistol primers and now it usually shoot's sub-MOA. Back when my kid's were little, they called it the 'penney shooter' as it is accurate enough to hit pennies at 100yds.
A buddy bought the same rifle, and with the Timney Spring & Sear kit and Lilgun powder, it is also a very good shooting rifle.
I have read quite a few stories about the 2 piece bolt and shimming it to increase accuracy, but our bolts are stock.
