by Vol. Formula:
When I attended the 60th Dipoloma Course at the Siebel Institute in 1988, I visited Victor Ecimovich, then the Brewmaster at Goose Island in Chicago. Vic had a little booklet called, "Schwartz Tables," and he used it to calculate the alcohol level of his beers.
I asked Vic where he got it, and he told me he got it from Siebel. I asked at school, and they told me they only had a few copies left, but I got one.
Examining the Schwartz Tables, I noticed a pattern. I converted the tables into Factors, and I extrapolated estimates for all those marvelous big gravity beers that were "off the charts" for the booklet's tables.
The formula was slightly logarithmic, but below is what I came up with. I have successfully been using my Schwartz Factors since 1989.
How to Use these Schwartz Factors:
Use a good temperature-corrected Plato hydrometer.