As far as the casing goes, the cartridge for the .357 Sig is
basically a 10mm auto case shortened with a neck capable of receiving a 9mm
bullet. While the case is a little longer than the .40 S&W, many guns
chambered for the .40S&W can be retrofitted for the .357 Sig by replacing
the barrel and recoil spring. The first gun actually made for the .357 Sig round,
however, was the SIG p229.
With regards to usability, many government and law
enforcement agencies have adopted guns chambered in the .357 Sig. In fact, the
Texas Department of Public Safety was the first agency to use this round in
1998. Since then, many gun manufacturers have produced pistols that chamber
this round, including the Glock 31. Many agencies that have adopted this round
allow agents a choice between this and a 9mm. Many, however, still opt for the
9mm solely because the guns tend to be lighter and carry more rounds.
Each box contains 2,500+ once fired brass shell casings. This is unprocessed range brass sourced from commercial shooting ranges. It has not been cleaned or resized and still contains the spent primer. This brass contains different manufacturer's headstamps. It is recommended that all brass be inspected prior to being reloaded and fired.