I shall talk to some of our scientists later and get you the V of D for TNT and some of the common fillings.
Just go to my web site page http://nigelef.tripod.com/ammo.htm there's a table there.
The overwhelming influence on where splinters go is angle of descent, a moment's mental modelling will reveal this.
30 yds is about effective splinter dist, basically it reflects splinter density, hence larger shells are greater, smaller less. Of course in WW1 fragmentation wasn't that great because the ratio of HE to metal was very low. Safe distance is much greater and is the dist where you could still get some large pieces of metal. The abolute distance used on firing ranges in UK is greater still and reflects heroic assumptions about how far a splinter might go.
The shrapnel distance is the effective distance from the point of 'burst'. Bethel states that for heavy field guns (ie 60-pr) this could be quarter of a mile, ordinary field guns were less. Obviously there's two factors here, bullet weight (ie carrying power) and angle of descent. Bethel also states the usual initial velocity provided by the bursting charge to the bullets was only 150 - 200 fps. The other issue about effectiveness is target posture, men lying down presented a much smaller target than those standing up.
The French used a very flat angle of descent with their 75mm because it had high velocity, Germans used a steep angle, partly because of their guns and partly doctrinal, UK was in between.