Okay, 100 (give or take) copper chests:

Run 1 - 21 copper, 5 silver, 3 gold
Run 2 - 24 c, 5 s, 3 g
Run 3 - 21 c, 6 s, 3 g
Run 4 - 18 c, 5 s, 3 g
Run 5 - 23 c, 5 s, 3 g