I'm not really sure what you're getting at but you consider 5,200 fps low?
G's are a measure of acceleration. A rifle bullet will have an acceleration rate in the neighborhood of 9,000 G's.
[edit on 3/8/2010 by Phage]
U. S. ARMY MATERIEL. COMMAND
BALLISTIC RESEARCH LABORATORIES
ABERDEEN PROVING GROUND, MARYLAND
Since July 1964, the gun was lengthened and a steel Martlet 38 was
successfuly fired1 7 at 8000 g's and attained a muzzle velocity of 5200
feet per eecond. The low mass fracti%n aasociated with the metal bodies
has been raised by introducing the use #-\f fiber glass bodies.
REVIEW OF THE HIGH ALTITUDE RESEARCH PROGRAM (HARP)