Increased capacity ammunition magazine

A pistol magazine, comprising:

• a metallic tubular body defining a hollow interior and having a forward wall, a rearward wall, a first side wall, a second opposite side wall, an open top with feed lips, and an open bottom,
• a follower,
• a spring,
• a removable closure member enclosing the open bottom and removably retaining the follower and spring in the body,
• at least one spacer associated with the forward wall and extending forwardly therefrom,
• an edge associated with at least one of the side walls and configured to interact with a magazine catch of a polymer frame pistol configured to accommodate a single stack polymer or polymer-over-metal magazine,
• a first interior dimension between interior surfaces of the forward and rearward walls dimensioned to fit 9×19 mm cartridges,
• a second interior dimension between interior surfaces of the side walls dimensioned to fit 9×19 mm cartridges with a staggered arrangement of the cartridges,
• a first exterior dimension between a forwardmost surface of the at least one spacer and a rearwardmost surface of the rearward wall matching the corresponding exterior dimension of the single stack polymer or polymer-over-metal magazine,
• a second exterior dimension between exterior surfaces of the side walls matching the corresponding exterior dimension of the single stack polymer or polymer-over-metal magazine, and
• the body having a height dimension configured to fit within a handgrip of the polymer frame pistol and to locate an uppermost edge of the removable closure member directly adjacent to a lowermost edge of the handgrip when the magazine is inserted into the handgrip.