Complex sentence: Using its pump action shot gun with its normal ballistic ammunition it literally did little if any damage to the opposing Gundam and was quickly discarded after seeing its poor effects, and its chain mines only blew off its external armor and half of its V antenna.
Split into simpler sentences: Using its pump action shotgun with its normal ballistic ammunition it did little if any damage to the opposing Gundam and was quickly discarded after seeing its poor effects. Its chain mines only blew off its external armor and half of its V antenna.