After I got home, I noticed one bucket was noticeably heavier than the other two. I weighed all 3 buckets - 4258 grams, 4263 grams, 5066 grams. Opened all 3 and one bucket definitely had more rounds in it.
So I emptied one bucket to get empty weight, weighed 30 rounds to get a per round average weight. Subtracted the empty bucket weight, divided by the per round weight. First 2 buckets were 350 rounds (+/- 1), the third bucket calculated at 420 rounds. 70 more rounds for free ain't bad!
