An ultra-short, high-density, perforating gun for use in a well casing includes a gun carrier extending along a longitudinal axis, only 2 charges located inside the gun carrier, the only 2 charges being positioned in a single plane transverse to the longitudinal axis, and a charge holder configured to carry the only 2 charges, the charge holder configured to be inserted into the gun carrier. The gun carrier ranges in length from 4 inches to 11 inches. A diameter of the gun carrier ranges from 1 to 4 inches, and wherein at least one charge of the only 2 charges has a liner that has a subtended angle from 100° to 120°.