Ammunition magazine and resilient member

A magazine configured for storing and feeding ammunition cartridges to a weapon comprising:

• a casing which comprises an upper end and a lower end;
• a floor plate situated near the lower end;
• a follower adjacent the floor plate;
• and
• a magazine spring inside the casing which comprises
• a first end connected to the follower,
• a second end connected to the floor plate, and
• a plurality of coils, each of the plurality of coils including
• a first segment having a first radius,
• a second segment having a first length adjoining the first segment,
• a third segment having a second radius adjoining the second segment, the second radius being greater than the first radius, and
• a fourth segment having a second length adjoining the third segment, the second length being approximately equal to the first length,
• wherein the second radius divided by the first radius defines a coil ratio, and the coil ratio is between approximately 1.1 and approximately 1.5.