Achieving 100% compaction on base rock is more about finesse than brute force. I’ve had good results using a rubber tired asphalt roller. Place the base in 6” to 8” lifts, add water until the material is a little juicy, then make about 6 to 8 (actual number may vary) passes with the rubber tired roller, finish with a single pass with a smooth drum vibratory roller (just to smooth things out). Avoid excess handling of the material; this can cause segregation which will not help your density.