A tool for implanting an inflatable penile prosthetic cylinder includes a barrel having a solid central portion and a groove formed in an exterior side surface of the barrel between a first convex curved exterior surface and a second convex curved exterior surface of the barrel. The groove extends to and forms an opening at the distal end of the barrel and forms a cavity extending into the barrel from the exterior side surface toward the solid central portion. The cavity has a first gap dimension measured at the exterior side surface that is smaller than a second gap dimension measured inboard relative to the exterior side surface of the barrel.
