The 55 km range of G5 is only through VLAP, not with regular shells. With regular shells, its 39 km at base bleed performance or 35 km in normal condition.
Now if we compare G5 and ATAGS, G5 is 155/45 as opposed to 155/52 caliber ATAGS.
G5 weighs at 13+ ton whereas ATAGS weighs at 12tons.
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