It is hard for me to nail down one favorate 308 load. I have had so many of them over the years.
That said, there has definately been a pattern of some loads that have worked very well in multiple 308's. Probably my best rifle to rifle load has been 43-44 grains of RL15 under the 190 SMK. This has been a SOLID 1/2 to sometimes sub 1/2 MOA performer from 100-1000 yards.
42 grains of RL15 under the 178 AMAX was about the most surgical load I have ever shot. My best 100 yard, 300 yard and 800 yard groups in ANY rifle/load combo were all fired with that load.
My best 1000 yard groups have been fired with the 155 AMAX. I forget the powder and charge. 3.5" with a consistent 4.5-5 MOA 1000 yard performance.
The 178 AMAX over 45.0 of N540, the 168 AMAX with 46.0 of N540, and the 175 SMK over 43.9 N540 (BR2 Primers) have all been scarey accurate.
My current 'pet' load is 46 grains of N550 under the 208 AMAX with CCI250 mag primers. 2600'/sec with nearly 1000'# at 1000 yards in standard air density.
One other sweet all around load that comes to mind was 42.0 of BENCHMARK under the 155 AMAX. Only 2750ish FPS but 1/2 to sub 1/2 all day, any day every day literally. That was my one and only 308 load for nearly 2 years and I NEVER had one bad day at the range or field with it. Those bullets just always seemed to hit their mark. Never had to make sighting adjustments etc....Just an all around sweet load. My only complaint was construction and energy, or lack therof.
As far as factory, I hqave not shot much of it but the Federal GMM 168 SMK have always shot bug holes at 100 yards and 1/2 to sub 1/2 MOA to 600. I am of the opinion that if your 308 wont shoot GMM 168's well, there is something wrong with your 308.
M