This impressive weapon is best fired after mounting it on firm ground.Final Fantasy Tactics A2: Grimoire of the Rift description
Solid Bazooka is a mid to high-ranked weapon for Barret, providing 61 Attack, 100 Atk%, 15 Magic, is Long Range, and provides 4 linked materia slots with normal growth. It can be bought for 16,000 gil at Costa del Sol after obtaining the Highwind.
Massive Bazooka is a high-ranked hand-cannon that provides 29 Attack, has 7 range, and teaches the abilities Mortar for 200 AP to the Cannoneer and Ether Boost for 350 AP to the Flintlock. It can be obtained from the Bazaar from the "Forgotten Firearms C" category.