How to Convert the Glock 33 to .40
- 1). Check the action of your G33 pistol to make sure the weapon is unloaded. Remove the magazine.
- 2). With one hand hold the top of the slide and -- with your other hand -- pull down the slide-locks located on each side of pistol just above the trigger.
- 3). Pull back the slide approximately 1/10 of an inch and immediately push the slide forward; the slide assembly will separate from the lower receiver.
- 4). Turn over the slide and remove the spring assembly. Lift the .357 SIG barrel out of the slide and replace it with a .40-caliber barrel (built for a G27).
- 5). Reassemble the G33 pistol.
