I think Jim Watson has the explanation, 30.5 moa sounds more like it. As he says, just a slip of the lip.
I ran the numbers on a ballistic calculator I've found to be quite reliable (it's at www.biggameinfo.com
) and it came up with 32 moa. This is at 1,000 feet elevation, temperature of 59 degrees and reticle 1.5 inches above the bore.
None of these ballistic calculators are perfect as there are so many variables, but as has been said earlier they can at least get you on paper and save a lot of time.