Official map hex size

Some measurements and calculations for Battletech maps that may interest you:

I tried to find information about official printed maps hex sizes:

• Rick Raisley, maker of Heavy Metal Map, writes that a hex measures "Right at 1.3" over flats. Basically, a standard map sheet is 22" tall, and has 17 hexes in that distance, which works out to 1.2941" across flats, and 1.4943" across points." (Heavy-Metal-Forum) [1.2941" * 2.54 cm/" = 3.287014 cm]
• Sarna.net states: "On a standard mapsheet the hex size as originally printed is approximately 1.25 inches." [~3.175 cm] also "The printed size of a standard mapsheet is 22 inches by 18 inches (not 22 by 17 as many rulebooks suggest)." (Sarna) [55.88 cm x 45.72 cm, not 43.18 cm]
• I made some measurements over 8 hexes (flats) on my official maps from various eras (FASA, wizkids, etc.) These yielded 26.30 cm, 26.33 cm, 26.37 cm, 26.47 cm, 26.56 cm and so on and also varied quite a lot on the same map depending on the direction I measured (vertical, or 30 degrees either way from horizontal). These measurements divided by eight (for a single hex) yield: 3.288 cm - 3.320 cm
• The variations in height of official printed map sheets is not that large, however some width measurements were 43.4 cm (obviously bad map from wizkids era with edge hexes cut off), 44.7 cm , 45.4 cm, 45.8 cm (non-obviously bad maps). 
• I tried to replicate Rick Raisley's calculation for non-vertical orientations:
  There are 16 full (15 full and 2 halves) hexes in an oblique row. Since these hexes overlap, every hex only contributes 3/4 of its width across points. So the map sheet is 12 (= 16 * 3 / 4) hexes wide if hexes are laid point to point. The relation between width across flats and width across points is wf = sqrt(3) * wp / 2 = 0.866025403784439 * wp (wikipedia)
  If we assume the 18" figure is correct [45.72 cm] then width across flats derived from map width is 3.2995568 cm (~= 45.72 cm / 12 * 0.866025403784439) [Rick service: ~1.2990"]
• Using my (non-obviously bad) official printed map width measurements: 3.226 cm - 3.305 cm

If we accept the standard (17x16 hexes on a 22"x18" sheet of paper) that defines top-to-bottom width as 3.287014 cm and horizontal width across points as 3.81 cm, we end up with slightly asymmetrical hexes.

Since I am in Germany, thus lacking 22"x18" paper and printer, and personally like metric measurements and symmetry, I will use 33 mm across flats in all directions as my standard. [Note: For 1 metre this differs by 0.6 mm from the 1.3" across flats standard.]