The HK21 is a machine gun derivative of the G3 rifle. The HK21 is a general-purpose machine gun manufactured by Heckler & Koch that chambers the 7.62x51mm NATO round.
Although the original HK21 itself does not appear in the Rainbow Six universe, there are variants of the weapon that have:
- The HK21E is a magazine-fed variant chambered in its native 7.62×51mm NATO caliber.
- The HK23E is 5.56x45mm NATO conversion of the HK21E.
- The G8A1 is a German military designation of the light machine gun, coming with the modifications of an HK11A1.
The HK21, HK21E, HK23E and G8A1 are categorized as light machine guns in the Rainbow Six universe.
Based on the 7.62 G3A3 framework, the 7.62mm 21E3 LMG is a light machine gun firing the 7.62x51mm round from a 100 round box magazine. This round packs more punch than the 5.56x45mm round. In addition, the 7.62mm 21E3 LMG has a single shot and three round burst option. It is more accurate than the M249 SAW, but is harder to control when moving around. As with the 5.56 M249 LMG, this weapon is best used from a stable firing stance.
Two variants of the HK21 are featured in Tom Clancy's Rainbow Six 3: Raven Shield: the 21E and 23E.
The 21E is a weapon featured in Tom Clancy's Rainbow Six 3: Raven Shield.
The 23E is a weapon featured in Tom Clancy's Rainbow Six 3: Raven Shield.
- "This all-purpose machine gun with its box magazine linkless feed system and three round burst capability is a staple in the Rainbow arsenal. Normally the M73E uses the Scope or Red Dot attachments."
— In-game description
The M73E is a weapon featured in Tom Clancy's Rainbow Six: Lockdown.
In the PC version of the game, the M73E is the standard weapon of Renee Raymond.
The M73E is a weapon featured in Tom Clancy's Rainbow Six: Critical Hour.
The 21E is a weapon featured in Tom Clancy's Rainbow Six: Vegas.
The 21E is a weapon featured in Tom Clancy's Rainbow Six: Vegas 2. Since Vegas 1 and 2 share the same engine and models, the weapon appears in the same configuration as its Vegas 1 counterpart.
- "GSG 9 LMG, accurate in short range. Capable of long range controlled fire."
— In-game description
- In Tom Clancy's Rainbow Six: Vegas and its sequel, the fire selector for the 21E is erroneously locked on safe at all times.