I would suggest that if you wanted to use SABOT rounds to replicate a real thing, the SABOT would do less damage than an equal weight AC version, but have double the ammo. SABOT is lighter than an equal round using the entire chamber after all, it packs the round to fit the larger shell size.
Thus, LBX Sabot dont lose half their bin, but deal damage based off the average cluster size of the LB while retaining the exact same crit roll bonus. A 3 point LB5X SABOT with 20 shots per ton, versus a 5 point AC/5 AP with 10 shots per ton.