Like i expected the fighterbomb projectile with both material #'s set to 777 will do fine, everything gets pushed w/o damge (unless they hit something else that is). You can mess aropund with the radius, forceonexplosion and explosonforce settings and alike, im not familiar with those settings but i do know higher numbers give better results
Its easy to try thing yourself, fire up the debugger in windowed mode, and pick a map.
Then work like this in the commandline:
ObjectTemplate.active [weapon] (i used the colt)
Objecttemplate.projectiletemplate [projectile] (i used fighterbomb)
ObjectTemplate.active [projectile] (fighterbomb in this case)
ObjectTemplate.forceonexplosion (if you type a new number here it will be set, if you press enter right away you get the original value)
ObjectTemplate.explosionforce[ ,max,mod] (same goes here)
ObjectTemplate.othersettingyoudliketochange
Object.create Us_Assault
Now pick up the kit that spawned infront of you when you typed in the last line, and see the results. If you want to change it again, start over at the first blank line i put in and change values, then respawn the kit and see the results. I most cases a new object has to be created in order to see changes, already spawned objects dont usually get updated (there seems to be a command for that, but it makes my pc lockup)
Goodluck