LB-X AC's don't get full use of their range as things stand right now. Lore wise they are meant to be LONGER ranged than standard AC's, yet still spray a target with frag....
To me the best way to realise this system is with an airbursting frag warhead with proximity fuse.
That is to say, the round travels most of the way to a target as a solid shell, (assuming we are firing at max range here), then about 90m from the target, the shell explodes, throwing a cone of frag at the target.
Works with LBX's of all calibers, just scale max range, detonation distance-to-target, and cone spread.
Obviously if fired from point-blank range,(as in, inside the distance to taget the shell would normally burst at), the shell bursts as it leaves the barrel, and we get what we see now with the LBX10.
Small edit: Changed "Abstain" to "Other" in the poll. If you do choose "Other", put a comment below, I'd like to hear other ideas.
Edited by Egomane, 12 April 2013 - 12:11 PM.
Changed third answer to "Abstain"