RE: 777: 2 Pellets vs. 3 Pellets
For the most part I do not believe that all of 3 pellets will burn in the barrel except with heavy bullets.
If you prefer pellets 2 will most often be the most accurate.
If you don't mind trying loose then try every thing from 100 to 120 loose and stay with the most accurate load,quite often that will be 110. Lee