The Rambo IV machete was John Rambo's main weapon in the 2008 film Rambo IV. Unlike the previous Rambo film knives, which were Bowie style knives, this is actually a much longer and thicker machete. Also, unlike the sophisticated knife designs of the earlier films, this one is a primitively built golok that was forged in a haste by Rambo himself to be used to rescue the Christian missionaries who were kidnapped by the Tatmadaw Army right after he throws away his previous knife in the fire after blowing and burn the boat of the pirate that he killed.
It was designed by Rambo film veteran Gil Hibben, who also produced an unsuccessful prototype for the film, dubbed the "Big John" machete, which proved to be so popular that he still makes it available for manufacture.
Unlike the other expertly crafted survival knives seen in the other films of the series, this one was made to look crude and slapdash. This design is that of a primitively built Asian golok machete made out of a single slab of D2 carbon steel from a truck spring. The knife is 1/4 of an inch thick and has a full tang. The knife has a flat grind, which means that it is beyond razor sharp. Its handle is wrapped in cordage, similar to the first two knives, however this knife has a handle made of electrical tape rather than string (although some unofficial replicas use paracord instead). There is a hole punched into the middle of the handle guard and a leather string lanyard is tied around it.
Its sheath was actually constructed from the Rambo III Knife sheath, which would explain its aged appearance. In the original script, it was forged in a haste after he tossed away his Rambo III Knife into the fires of the burning Burmese army boat, which he intended to symbolize his end to killing. In a test scene, they used a placeholder Rambo II Knife.
Sylvester Stallone actually stayed up all night filming the scene of him building the knife like you see in the film, although due to time constrictions, he had to do it all at once without cooling the blade. They went through eleven pairs of heat protective gloves over a period of about fifteen hours due to this. Sly claims after making the knife, he had a rather warm handshake. This scene was inspired from a deleted scene from Rambo III where he builds the famous Bowie knife. Since Stallone wanted to include Rambo actually building his own knife, he incorporated it into the story of the fourth film. Stallone also felt that the scene would help Rambo to vent his frustrations while thinking about his purpose in life.
Rambo was seen hammering the raw steel on an anvil before sticking it into the ashes of a fire. He let it sit and become hotter and therefore easier to shape before removing it and hammering it some more. Rambo repeated this process a couple more times before sticking the blade in a feeding trough, cooling it rapidly. He withdrew it, and noticed that the blade was still not cooled down yet. Later in the scene where he rescues the missionaries, Rambo had it drawn and held close to his chest in case of enemy soldiers when he was rescuing the missionaries from the Tatmadaw Army camp and this was pretty much the only scene Rambo was seen with it out. There is a scene in the extended cut where Rambo uses the machete to cut Sarah's bonds after ripping Lieutenant Aye's throat out.
Rambo used the knife first to decapitate the head of the Browning M2 Aircraft machine gunner. The scene was so poorly lit in early trailers that it appeared to audiences that he had punched off the gunner's head. Rambo tailored the sheath from his Rambo III knife to fit the machete and kept it on his belt. Rambo had to cut a hole in the bottom of the sheath where he kept the drop point to accomodate the sheer length and curveture of the blade. Unlike the other knives which were practically integral to his very survival, this knife wasn't used often in the film, and the most famous scene it was in was when Rambo used it to disembowel Pa Tee Tint and slice off four of his fingers.
There are three different official replicas of the Rambo IV mini-machete. The first is a Gil Hibben handmade machete. There is another replica made by Master Cutlery, or the Hollywood Collectibles Group, and another made by United Cutlery. Master Cutlery's machete sheath is plain brown leather, United Cutlery's is reconstituted black leather, and the Hibben handmade is handmade genuine aged leather.
The Master Cutlery replica is different from the other two because it features a genuine leather handle wrap, whereas the others use electrical tape. They are all also made of different materials. The Hibben handmade is D2 Carbon steel, the Master Cutlery is 1060 Carbon steel, and the United Cutlery is 1090 Carbon steel. Other than these the replicas are fairly similar, except for their finishes. The Hibben handmade and United Cutlery are both semi-polished and the Master Cutlery's finish is rough.
All these replicas are quite expensive, ranging around eighty dollars. There are some knock-off knives, though, which cost much less money.