A sealant tube for use in a pneumatic sealant gun for reducing or eliminating air bubbles in the sealant being dispensed. The sealant tube may fit within a hollow sleeve of the pneumatic sealant gun and contains sealant and a slidable plunger. The tube body may include an inner surface, an outer surface opposite the inner surface, a first opening, a second opening opposite the first opening, and pressure release openings formed through the tube body, such that air from a pressurized air source flows into the tube body and between the tube body and the hollow sleeve during use of the pneumatic sealant gun, equalizing pressure on the inner surface and the outer surface of the tube body. A seal or gasket may also be located proximate the second opening of the tube body, for forming an airtight seal between the hollow sleeve and the tube body.