The MP5 submachine gun is a 9mm submachine gun with a retractable stock designed for military and police applications. John Rambo was given one by the CIA to use as his main firearm when he went into Vietnam, along with a Compound bow. The gun was too recent and upgraded for use in the Rambo films, however, which typically use weapons seen in wars like Vietnam and WWII.
Considered the "Rolls-Royce of submachine guns", the MP5 gathered great interest in the mid-1980s since the SAS Iranian Embassy siege and began being used by armies and SWAT teams across the globe, as well as in famous blockbusters such as Die Hard. They are one of the most commonly-seen weapons in American cinema today.
John Rambo is seen loading one issued to him by his CIA contractors, but he loses it when he cuts his equipment loose during the failed drop so he can parachute into Vietnam safely. His MP5 was fitted with a 3x scope. He is loading the gun with pre-fired dummy rounds in the scene.
- The lack of a barrel lug identifies the weapon as an HK94A3 rather than an MP5A3. The HK94 was a civilian version of the MP5, which fired in semi-automatic mode only. Professional Hollywood armorers in the 1980s would legally convert these to fully automatic and then saw off the long carbine barrels, mocking-up these guns to appear as combat weapons.