How to Convert Glock 33 .357 to .40

The Glock 33 pistol can be quickly modified to fire .40 caliber bullets by simply replacing the barrel. The Glock 33 is a small handgun, classified as a sub-compact, that uses .357 SIG ammunition. According to the technical support staff at Glock, the pistol can be converted by switching the barrel with one from a Glock model 27 (the Glock sub-compact pistol chambered for .40 caliber). The same procedure can be applied to convert the Glock model 27 to a .357. Before working on your pistol, make absolutely sure that the weapon is unloaded.

Things You'll Need

• Glock model 33 pistol
• Barrel for Glock model 27 pistol

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Instructions

1. • 1

     Remove the magazine from your pistol and disassemble your Glock 33.

   • 2

     Replace the .357 SIG barrel with a .40-caliber barrel (designed for a Glock 27) and reassemble the weapon.

   • 3

     Place the magazine back into the weapon. The magazine for a .357 SIG will accommodate .40-caliber bullets. The only difference between the two is the diameter of the projectile; the diameters of the two bullet casings are identical.