The Beretta 92FS--also known as the Beretta M9 in military circles--replaced the venerable old Colt 1911 as the primary sidearm of the United States Military in 1985, and since then has become one of the most recognizable weapons in the world. The .40 caliber Beretta 96 is essentially a re-vamped Beretta 92FS--identical in appearance, but boasting a heavier caliber payload and more stopping power than the 9mm Beretta M9. Disassembling a Beretta .40 caliber is a relatively simple affair, requiring no tools or parts beyond your hands and a good grip.
Eject the magazine and pull the slide back several times to ensure that there is no cartridge loaded in the firing chamber. This should be your first step whenever you are working on any type of firearm.
Press the "release" button on the right-hand side of the Beretta--located just beneath the barrel towards the front of the gun--and swivel the takedown lever on the left-hand side of the gun downwards.
Push the slide all the way forward off of the frame.
Use your thumb to push the recoil spring forward--towards the barrel--slightly, then lift up to remove it from the slide.
Press the small locking pin on the back of the barrel inwards, then draw the barrel up and backwards out of the slide.