US Patent 10001337 Composite multi-lobe projectile barrel

A composite multi-lobe barrel is disclosed for directing the path of a dischargeable projectile. The multi-lobe barrel incorporates a plurality of longitudinal stiffening rods into a composite overwrap around an inner liner to enhance axial stiffness. The barrel is comprised of an inner liner defining an axial bore; a plurality of polymer matrix composite (PMC) stiffening rods equidistantly disposed around the inner liner and a PMC outer shell enclosing the stiffening rods. In one embodiment, a PMC inner wrap surrounds and is in direct contact with the inner liner, with the stiffening rods arranged equidistantly around the inner wrap, with this structure enclosed by a PMC outer shell.