In order for railgun technology to be relevant to the Infantry, the design of the projectile must incorporate the following three concepts: an effective ballistics package, geometries for aerodynamic stability; and a non-parasitic conducting armature. I designed an effective 30mm and scaled 40mm projectile which incorporates the aforementioned concepts. My ballistics analysis concluded with two AUTODYN(Trademark) finite-element computer models that refined theoretical estimates for target penetration. The proposed railgun projectiles were effective in penetrating 100 mm of Rolled Homogenous Armor and in perforating 8 inches of Double Layered Reinforced Concrete. My theoretical analysis in aerodynamics predicts in-flight stability with a minimum static margin of approximately two percent. The analysis and modeling of the electromagnetic launch resulted in an adequate design. For this analysis, I used three Comsol Multiphysics(Trademark) finite-element computer models. The modeling results validated fundamental railgun equations. The final projectile design concluded with a 3 m barrel and is characterized by the following parameters: conducting rails with an inductance gradient approximately equal to 0.38 H/m; an average temperature rise in the rails of 20 C per shot; an effective current of less than 2 MA; and a projectile launch velocity of 1100 m/s.