What is the difference in a “wildcat” and an “improved” chamber?
A “wildcat” is a cartridge that has to be made from an existing brass by shortening or modifying the existing brass just to be able to fit it into the chamber. An “improved” chamber is one where the improved brass is made by simply firing the cartridge in an improved chamber and allowing the brass to form itself to the chamber. Firing a 220 Swift cartridge in a 220 Swift Improved chamber will give you a fire-formed piece of 220 Swift Improved brass. Some refer to this as “blowing out” the brass. Once formed, the case now has less body taper, more defined shoulders and an increased powder capacity. Back to top.
