go to this thread, you'll find the difference between the actions / models by HVA; http://www.canadiangunnutz.com/forum/showthread.php?t=247277&highlight=hva
One of the differences between the M94/96/38 and the FN made M98 is that the M94/96/38 is a small ring, just like the others M93/M95, designed before the coming of higher pressure rounds (the 7.92X57JS or 8X57JS the forecomer of all high pressure rounds, wich was totally redesigned in 1905 and brang the M98 large ring - the pressure of the round was raised from about 47 000 PSI to 57 000 PSI MAP).
The later FN M98 "H" type were re-designed when NATO wanted to find a new round wich will achieve the higher velocities and pressure or equal the military loads of the time in a shorter case with new powders. Most of these experimental rounds were averaged at 62 000 to 67 000 PSI (proof loads) and in 1952, when they finally set (under U.S. pressure to adopt it) on the 7.62X51, they also set the "working" pressure back to 50 000 PSI. But Winchester introduced the .308 Win, wich have a MAP of 60 000 PSI.
The FN H type was widely used, in it's commercial form, to handle the fury of the then top of the notch pressure wise Weatherby Magnums (the first wave, anyways).
All later designs from HVA (namely 1640 and 1900) were also made for the higher end of modern pressure range.
Good post Baribal. Just thought I would add that the 1900 was a push feed action and a completely new design for Husqvarna.