I'm packing medium-sized gravel (1.5"-minus crushed rock) in to holes, to provide a stable base for pier blocks in clay-rich soil. There are 30 holes, roughly 24" diameter, 18" deep.
I have a 10" x 10" hand tamper, but my carpenter friend said that would only work well on smaller rock. He suggested using a 4" x 4".
I have been tamping & tamping, and now my joints hurt, and I have a lot more tamping to do. Maybe my technique could be improved? Maybe I don't need to tamp as thoroughly as I have been.
I tried googling for tamping info, and mostly I came up with tips for making espresso. And every site that mentions tamping gravel just says "step 5: tamp gravel" and gives no further details.