Mike-
I got the .38/44 data from ballistics charts and articles that I've read over the years. I remember things!
Two quick sources that I just dug out are the very obvious source Keith's, "Sixguns", which has a manufacturers' ballistics list showing the .38 Special Super-X (the 1950's name for the .38/44) at 1175FPS with 150 grain bullet. You could get it in metal point or Lubaloy, and the tested bbl. length was five inches, the most common length for the .38/44 Heavy Duty S&W. However, that was probably a solid test bbl. they used.
I aso have a Remington catalog from 1963 and it shows the ".38 Special High Velocity" at 1090 FPS. The highest velocity for any .38 special round that I've seen is here, too, with a 110 grain bullet, Metal Penetrating, at 1320 FPS.
S&W advised me when I was still in high school in the early 1960's that these high velocity loads wouldn't blow up a M&P (Model 10), but that if very many would be fired, their .38/44 Heavy Duty or Outdoorsman were the appropriate guns to use.
I have never seen a .38/44 load at 1400 FPS; that's .357 Magnum territory. It is possible that certain writers may have developed handloads that would reach that velocity, but today, that would be considered overpressure for the round. There are certain men whose published handloads I just don't use!
By the way, anyone interested in the .38/44 should beat feet over to
www.smith-wessonforum.com They publish quite often on it there, and have shown some fine photos.
Lone Star