MG 3 machine gun

December 4, 2008

MG 42 MG 3
Caliber 7,92×57 7,62×51
Weigth 11,6 kg (gun) + 20,5 kg (Lafette 42 trpod) 10,5 (gun) + various tripods
Length 1219 mm 1225 mm
Length of barrel 533 mm 565 mm
Feed belt belt
Rate of fire 1200 – 1500 rounds per minute 700-800 or 1100-1200 rounds per mniute

mg3

With adoption of the MG 34 machine gun the Wehrmacht had the weapon that was envisaged some 20 years before, and the MG 34 bears the distinction of being the first practical universal (or general purpose) machine gun. While the MG 34 was good and practical, it was certainly not ideal. German experts wanted their machine guns to fire faster, while being simpler and less costly. A high rate of fire was desirable both for AA applications and for surprise flanking fire against targets moving through the battlefield. As early as 1937 HWaA issued a request for the next new universal machine gun,and three companies received development contracts – Johannes Grossfuss AG, Stubgen AG and Rheinmetall-Borsig AG. In 1939 a commission selected the Grossfuss-made MG 39 prototype for further development. Designed by engineer Gruner (often wrongfully referred to as Grunow) and small arms designer Horn, new weapon, in accordance with HWaA request, had a stamped steel construction, combined with locked breech, short recoil action. Initial trials suggested that the Grossfuss MG needed further development, and in late 1941 a small batch (about 1500 pieces) of improved guns was manufactured for troop trials as the MG 39/41.
The new machine gun, while being made to lower standards of fit and finish, proved to be quite functional and reliable (a feature that the much more “refined” MG 34 lacked, especially in the mud and snow of the Russian front). Subsequently, it was officially adopted as the MG 42, and production commenced later the same year.


In general terms, the MG 42 was a great success. It fulfilled the roles of a light machine gun on a bipod, a medium machine gun (on a newly developed Lafette 42 tripod), and an anti-aircraft machine gun, mounted in single and twin installations, ground and vehicle-mounted. It was relatively inexpensive to make and required less raw materials than the MG 34, and it was simple to maintain and use. On the minus side, it had a somewhat excessive rate of fire, usually quoted as 1200 rounds per minute, although German WW2 era manuals listed it as 1500 rounds per minute (25 rounds per second). This rate of fire resulted in excessive consumption of ammunition and rapid overheating. While the extremely rapid barrel change procedure allowed for sustained fire, the resulting accuracy left something to be desired; excessive vibration from recoil, combined with a short sight radius, resulted in degraded long range accuracy compared with earlier MG 34 and, especially, the heavy MG 08 Maxim guns. Nonetheless the MG 42 was an impressive and fearsome weapon, known among Allied soldiers as “Hitler’s saw”, for the sound of the firing which resembled the sound of a giant mechanical saw.
After the WW2 this weapon, unlike other wartime designs, lived on, as in 1958, the FRG (West Germany) re-instituted its official armed force, known as the Bundeswehr. Since the core of the Bundeswehr was formed of WW2 veterans, it was logical to adopt weapons which were already proven and familiar to the troops; and the MG 42 was one of such weapons. It was, obviously, chambered for a ‘non-NATO’ cartridge, but this was only a minor issue, as the 7.62×51 NATO and 7.92×57 Mauser shared the same cartridge base diameter, and were somewhat similar in ballistics. The real problem, however, was that Germany had lost most manufacturing facilities for the MG 42, so the newly reestablished Rheinmetall concern had to install production facilities from the ground up. The production documentation for original MG 42 machine guns was obtained from Grossfuss company and transferred to Rheinmetall (German government had to pay significant royalties to Johannes Grossfuns for manufacturing rights). Since the preparation for manufacture took some time, the FRG purchased some ex-Wehrmacht MG 42 weapons from other countries. Those guns were converted to 7.62 NATO by Rheinmetall and officially designated MG 2. The newly produced MG 1 guns went through a number of modifications, which resulted in the definitive MG 3 version, which still is rather close in design to the war-time MG 42, although made to much higher standards of fit and finish. The simplicity, low manufacturing cost and high effectiveness of the MG 3 attracted several other countries, which either bought the guns from Rheinmetall (such as Denmark), or obtained manufacturing licenses and build (or at least have built in the past) the same guns domestically (such as Italy, Iran, Turkey, Pakistan and Yugoslavia). In total, at least twenty armies have used or still are using the MG 3 and its versions. It must be noted that in some countries these guns were used under their “commercial” Rheinmetall designation MG 42/59.
mg3
The MG 42 is a short-recoil operated, air cooled, belt fed weapon which fires from an open bolt. The barrel is quick-removable, and can be replaced in less than six seconds by a properly trained crew, although an asbestos glove is required to remove the hot barrel. The action of the weapon is operated by the recoil of the locked barrel, assisted by a muzzle booster which uses pressure from the muzzle blast to increase the recoil impulse. Locking is achieved by a pair of rollers, which are forced outwards from the sides of the bolt head to engage cuts in the barrel extension. Locking (outward) movement of the rollers is controlled by the wedge-shaped front part of the bolt body; unlocking (inward) movement of the rollers by the cams made in the receiver. This is a simple and solid system which minimizes the length of parts that are under stress upon discharge, and also minimizes the strain on the receiver. On MG 3 machine guns, two types of bolts are available, with standard weight (about 650 gram) for fast rate of fire and with heavy weight (about 900 gram) for slow rate of fire. It must be noted that those bolts also are used along with different return springs.
The receiver and barrel jacket are made in one unit, and formed from a sheet of rolled steel, cut to shape by pressing and stamping, and then welded and pinned to form a gun housing of generally rectangular cross-section. The front part of the housing serves as a barrel jacket and has a number of oval cooling slots at all sides except the right. The right side of the jacket has one long slot which is used to remove the barrel. The barrel is held in place by a hinged lock, located at the rear of the opening in the right side of the jacket. To remove the barrel, the operator must first lock the bolt in the open position (cock the weapon), and then turn the barrel lock to the right and forward. This will release the barrel and bring its breech area out of the jacket, so it can be grabbed (using the issued asbestos glove or other heat insulation means if the barrel is hot) and pulled back and out of the jacket. The new barrel is then inserted all the way forward and lock then is snapped into place, bringing the barrel into alignment with the action.
The gun is fed using belts only. Feed direction is from the left to right; the feed is of the one-stage, push-through type. The belt is same as for the MG 34, with steel links with open pockets, assembled into non-disintegrating 50-round lengths. The same MG 34 type “Gurttrommel” 50-round drum-type belt containers can be used with the MG 42, and a new type of lightweight plastic 50-round belt container was developed in West Germany by HK and is now issued with MG 3 guns. The belt feed is operated by the reciprocating bolt which has a roller at the top of its body. This roller engages the cam track in the oscillating lever, located in the top-opening feed cover. The lever operates the belt pawls in two steps, on both opening and closing movement of the bolt, resulting in a smooth and positive feed. This two-step belt traction is particularly useful because the high rate of fire results in high-speed belt movement, and this system reduces the strain put on both the feed unit and belt links. Current production MG 3 guns can fire either non-desintegrating or desintegrating belts.
The trigger unit is of relatively simple design, and permits for automatic fire only. The manual safety is of the cross-bolt, push button type, located at the top of the pistol grip. The charging handle is located at the right side of the receiver, and is separated from the bolt group (it does not move when gun is fired). Each MG 42 was issued with an integral, adjustable bipod attached near the muzzle; MG 3 guns may have two points for bipod attachment, one near muzzle and another near the center of the gun. In the medium role, the MG 42 was used from the Lafette 42, a complicated foldable tripod with buffered cradle. A wide number of tripods is available for MG 3 guns, as produced in several countries.
The standard sights are open, fully adjustable, and mounted on folding bases. The universal tripod has provisions for mounting telescopic sights for long range and indirect fire missions.

Heckler-Koch HK UMP

December 4, 2008

Caliber: .45ACP, .40SW and 9x19mm Luger/Para
Weight: 2.1 – 2.2 kg empty
Lenght (stock closed/open): 450 / 600 mm
Barrel lenght: 200 mm
Rate of fire: 600 – 700 rounds per minute
Magazine capacity: 10, 25, 30 rounds
Effective range: 100 meters

ump-02

The UMP (Universal Machinen-Pistole = Universal Submachine Gun) had been developed by the Heckler & Koch company of Germany in the mid- to late- 1990s and first appeared on the markets in 1999. The key idea behind the UMP was to ceate lightweight and powerful submachine gun, that also will be cheaper than one of the J&K’s flagships, the MP-5. UMP, being targeted primary for USA law enforcement market, first appeared in .45ACP and .40SW chamberings, and later – in 9mm.

The UMP is a blowback-operated select-fire submachine gun, being fired from the closed bolt. The receiver is made from the polymer, the controls are fully ambidextrous. UMP can be fired in full-auto, in single shots, and in 2 or 3 round bursts (optional). UMP also has bolt hold-open device, which traps the bolt in the open position when the last round from magazine had been fired. UMP has side-folding buttstock and two set of picatinny rails – one on the top of the receiver, and the other – on the forend. These rails can accept wide variety of sighting and other equipment, such as red-dot sights, laser pointers, tactical grips and flashlights. The barrel has quick mount for snap-on silencer.

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Heckler – Koch HK MP7

October 24, 2008

Caliber: 4.6x30mm HK
Weight: 1.5 kg empty
Length (stock closed/open): 340 / 540 mm
Barrel length: 180 mm
Rate of fire: 950 rounds per minute
Magazine capacity: 20 or 40 rounds
Effective range: 150-200 meters

HK MP7A1

The HK MP7 Personal Defense Weapon (PDW) is a member of a relatively new class of small arms, called Personal Defense Weapons (PDW; such specialized weapons are build since the start of WW2). The PDW are intended, as name implies, to be a defensive sidearm for second-line troops, vehicle crews and other military personnel who normally not issued with assault rifles. Previously, these troops were issued with pistols or submachine guns, but proliferation of body armor in recent years made those guns ineffective. The first firearm, intended as “the new age PDW” and offered in that class was Belgian-made FN P90, and it had special low-impulse, high-velocity ammunition, capable of penetration of current military body armor and helmets at ranges of 100 meters and beyond, while being much smaller and lighter, than assault rifle. The HK MP7, originally known simply as HK PDW, is another entry in the PDW class, and thus is a direct rival to FN P90.

The HK MP7, first announced in 2000, entered production in 2001 and, by early 2007, is officially adopted by German military, as well as some German special police units, such as KSK, and also offered for export sales. The British Military Police issues HK MP7A1 to its personnel since 2005, and it is believed that some South Korean special forces also use MP7A1.

ksk with mp7

The HK MP7 submachine gun / personal defense weapon has layout of a typical compact submachine gun (or a large pistol), with magazine being inserted into pistol grip, with folding forward grip and telescoped buttstock. The action of the MP7A1 is somewhat unusual for weapon of such small size, since it is gas operated, rotating bolt design, which strongly resembles the action of the HK G36 assault rifle, suitably scaled down. The ambidextrous fire mode selector/safety switch allows for semi-auto and full-auto modes. MP7A1 it designed to fire special, high velocity ammunition, 4.6x30mm, that looks like scaled down rifle round. That ammunition is unique to the MP7 and another HK weapon, the HK UCP / P46 pistol.
The receiver of MP7A1, along with integral pistol grip, is made from the polymer with steel reinforcements. Top side of the receiver hosts a Picatinny-type accessory rail for sight mountings. Standard sighting equipment is usually a set of low-profile open sights on quick-detachable mounts, plus a collimating (red-dot) sight Additional rails can be installed on either side of receiver, next to its front end.  The MP7A1 could be fired single-handedly, or using both hands, either like the pistol or using a front grip. Telescopic buttstock can be extended to give additional stability. With buttstock and front grip are collapsed, the MP7 can be carried like any big pistol in the special holster, and can be effectively used in close combat.

The 4.6x30mm ammunition is loaded with pointed all-steel bullets with brass jacket. Bullet weight is 1.6 gram (25 grains) and the muzzle velocity is 725 m/s (ca. 2400 fps). Manufacturer claims the 100% penetration of the CRISAT body armor (1.6mm of Titanium plus 20 layers of Kevlar) at the distance of 200 meters. Other types of ammunition, including tracer, frangible, spoon-tip (rapid-tumbling for use against unarmored human targets), blank and trill (inert) also available for MP7A1; ammunition is currently manufactured in UK by BAE Systems / Radway Green plant.

different type of ammo

MP-5A2 MP-5A3
Caliber 9x19mm Parabellum (also .40S&W and 10mm Auto)
Weight, empty 2.54 kg 2.88 kg
Length 680 mm 490 / 660 mm
Barrel length 225 mm
Rate of fire 800 rounds per minute
Magazines 15 and 30 rounds

HK MP-5A2 with fixed stock and plastic S-E-F trigger group.

The Heckler und Koch submachine gun, MP-5, is one of the most famous and wide-spread firearms of its class, developed since the Second World War. Its development began circa 1964 under the company designation HK MP-54, or simply HK 54. In the 1966, German police and Border Guard adopted the HK 54 as the MP-5, and it was originally available in two forms – MP-5 with fixed buttstock and MP-5A1 with retractable buttstock. Some years later HK slightly upgraded the design of MP-5, replacing the sights (from flip-up open notch rear and blade front to drum-type diopter rear and hooded post front) and the muzzle (replacing the two-slot muzzle compensator to the tree-lugs QD silencer mount without compensator). Other improvements made over the time concerned the magazines (early type magazines were of straight box type, latter – of curved box type for improved reliability). The trigger units also were upgraded – from original stamped steel with plastic grip to the all-plastic units, integral with grip, and with various fire modes and marking. Over the years MP-5 were adopted by the huge numbers of police, security and military forces around the world, including the German police and border guard, British police and elite Army SAS units, American police, FBI, Navy and Marine Corps, and many, many others. MP-5 is still manufactured in Germany by the HK itself, and also licensed to Greece, Iran, Pakistan and Mexico. The only real rival to the MP-5 in the terms of proliferation across the world is the famous Israeli UZI submachine gun. Most interestingly, the German Army (Bundeswehr) did not adopted the MP-5, most probably due to the economical reasons, and turned instead to the… UZI submachine guns, made under license in Belgium.
The success of the MP-5 is outstanding. It is based on the high quality and reliability of the gun, great single-shot accuracy (thanks to its closed bolt action), great flexibility and, of cause, good marketing. It seems that no other modern SMG at this time can rival the MP-5 in popularity (UZI is not manufactured anymore).

HK MP-5N. Modern version developed for US Navy. Features plastic trigger group of latest design, with ambidextrous selector lever and “icon” markings. Barrel is threaded to accept US-made detachable silencers, in addition to HK standard three-lug mounts. Retractable buttstock of A3 configuration.

The MP-5, basically, is no more than the scaled-down version of the Heckler-Koch G3 battle rifle. It shares the same basic design with stamped steel receiver and the same roller-delayed blowback action, derived from the post-war CETME rifles. The trigger units are hinged to the receiver and are now available with various fire mode options,  including 2 (Safe, Semi-auto), 3 (Safe, Semi, Full Auto) or 4 (Safe, Semi, Limited burst of 2 or 3 rounds, Full auto) position levers, ambidextrous or not, and marked with letters, digits or icons. The MP-5 is always fired from closed bolt for improved accuracy, but this limits the amount of sustained fire due to the barrel overheating and resulting cook-off problems. To avoid this, MP-5 cocking handle could be locked in the rear position in the special slot, leaving the bolt in the open position, with no cartridge in the chamber. To commence the fire one must simply release the cocking handle from its notch and then pull the trigger. Modern MP-5 submachine guns are equipped with three-lug quick detachable silencer mounts on the barrel. Sights are similar to other HK models, and consists of the front hooded post sight and the adjustable for windage and elevation drum-type diopter rear sight. Special quick-detachable clamp mounts allows for installation of night, optical and red-dot sights if required. Standard magazine capacity is 30 rounds, but shorter 15 rounds magazines are available. Special versions were developed and manufactured in limited numbers during 1980s-90s for the US Law Enforcement market, chambered for more powerful 10mm Auto (10x25mm) and .40S&W (10x22mm) ammunition. These guns can be easily distinguished from more common 9mm models by straight box 30 rounds magazines, made from plastic.

Navy Seals with MP5N

While all of MP-5 can be fitted with silencers, there also a dedicated silenced version of MP-5, called MP5SD2 or SD3 (depending on the stock type). This version is equipped with non detachable integral silencer, and the vented barrel, to reduce the bullet muzzle velocity down below the speed of sound. The MP-5SD is intended to fire standard 9mm ammunition, not the special subsonic one.

Semi-automatic only versions of the MP-5 were once made for civilian market under the designation of HK-94, some with longer, 16 inch (406 mm) barrels, to conform with US laws. There also is an US company, called Special Weapons LLC, that is manufacturing semi-automatic, civilian MP-5 clones in various pistol calibers, including the .45ACP.

Visual difference between trigger units:
left -earliest type stamped steel with plastic grip (converted from semi-auto only civilian gun HK 94, with American markings on selector);
middle – early type all-plastic with S-E-F markings;
right – most modern all-plastic design of “A4” variation, with additional 3-rounds burst facility and icon markings.

Instruction video – Part 1

Instruction video – Part2

G36 G36K G36C
Caliber 5.56x45mm (.223 Rem)
Length (buttstock open / folded) 998 / 758 mm 860 / 615 mm 720 / 500 mm
Barrel length 480 mm 320 mm 228 mm
Weight empty 3.6 kg (3.3 kg G36E) 3.3 kg (3.0 kg G36KE) 2.8 kg
Magazine capacity 30 rounds standard
Rate of fire 750 rounds per minute

The Heckler und Koch G-36 assault rifle had been born as HK-50 project in early 1990s. The reason behind that project was that the Bundeswehr (the German army), after the cancellation of the G11 and G41 projects, was left with outdated G3 rifle and no modern rifle, compatible with the current NATO standards at hands. So, the famous company Heckler & Koch was set to develop a new assault rifle for the both German army and the export. The new rifle should have been a flexible, affordable and extremely reliable design. And a modern of cause. It seems that the HK succeeds in every respects with the G36. The new 5.56mm assault rifle had been adopted by the Bundeswehr in the 1995, and in the 1999 the Spain adopted its slightly different, export version, G36E as its standard infantry rifle. The G36 also found its way into the hands of various law enforcement agencies worldwide, including British police and some US police departments. So far I’ve heard very few complaints about this rifle, and a lot of good revives and opinions. In fact, the only complaints about G36 that I know are the overheating of the handguards during the sustained fire, and the loose of zero of built in scope on some G36KE rifles, used by US police. Otherwise it is a really fine rifle, accurate, reliable, simple in operations and maintenance, and available in a wide variety of versions – from the short-barreled Commando (some even said that it’s a submachine gun) G36C and up to a standard G36 rifle and the MG36 squad automatic (light machine gun).

G36K – carbine version with standard dual scope mount and the buttstock folded

The G36, in severely modified form, also is used as a “kinetic energy” part of the US XM-29 OICW weapon. It also appears that in this form it also can be adopted by US Army as the separate XM-8 light assault rifle, to replace in the near future not so successful Colt M4 carbines, which are now in service with US military.

Technical description.
From the technical point of view, the G36 is a radical departure from all the previous HK rifles, based on the proven G3 roller-delayed system. The G36 is a conventional gas operated, selective fire rifle, made from most modern materials and using most modern technologies.

The receiver and most of the others external parts of the G36 are made from reinforced polymers, with steel inserts where appropriate. The operating system appears to be a modification of the older American Armalite AR-18 rifle, with its short stroke gas piston, located above the barrel, square-shaped bolt carrier and the typical rotating bolt with 7 locking lugs. Of cause, there also are many differences from the AR-18. The bolt carrier rides on a single guide rod, with the return spring around it. The charging handle is attached to the top of the bolt carrier and can be rotated to the left or to the right. When not in use, the charging handle aligns itself with the axis of the weapon under the pressure of its spring, and reciprocates with the bolt group at the top of the receiver. The gas block is fitted with the self-adjustable gas valve, that expels all the used gases forward, away from the shooter. The ejection window is located at the right side of the receiver and features a spent cases deflector to propel the ejected cases away from the face of the left-handed shooter.

All the major parts are assembled on the receiver using the cross- pins, so rifle can be disassembled and reassembled back without any tools.

The typical HK trigger unit is assembled in a separate plastic housing, integral with the pistol grip and the triggerguard. Thanks to this feature, a wide variety of firing mode combinations can be used on any rifle, simply by installing the appropriate trigger unit. Standard options are single shots, full automatic fire, 2 or 3 round bursts in any reasonable combinations. The default version is the single shots + 2 rounds burst + full auto. The ambidextrous fire selector lever also serves as a safety switch.

G36C – Compact or Commando version with open (iron) sights installed on the Picatinny rail

G36 is fed from the proprietary 30-rounds box magazines, made from translucent plastic. All magazines have special studs on its sides, so two or three magazines can be clipped together for faster reloading. The magazine housings of the G36 are made as a separate parts, so G36 can be easily adjusted to the various magazine interfaces. By the standard, the magazine release catch is located just behind the magazine, in the G3 or AK-47 style, rather than on the side of the magazine housing (M16-style). A 100-round Beta-C dual drum magazines of US origins also can be used (these magazines are standard for the MG36 squad automatic versions of the G36).

The side-folding, sturdy skeletonized buttstock is standard on all G36 rifles. It folds to the right side and does not interfere with rifle operation when folded.

The standard sighting equipment of the G36 consists of the TWO scopes – one 3.5X telescope sight below, with the second 1X red-dot sight above it. The sights are completely independent, with the former suitable for long range accurate shooting, and the latter suitable for the fast target acquisition at the short ranges. Both sights are built into the plastic carrying handle. The export versions of the G36 are available with the single 1.5X telescope sight, with the emergency open sights molded into the top of the carrying handle. The subcompact G36K Commando version is available with the integral Picatinny-type scope and accessory rail instead of the carrying handle and standard sights.

The standard G36 rifles can be fitted with the HK AG36 40mm underbarrel grenade launcher. It also can be fitted with the bayonets. Interestingly enough, G36 uses an AK-74-type bayonets, which are left from the now non-existent NVA (East Germany Army) stocks.

Caliber: 7.62mm NATO (.308 win)
Action: Roller-delayed blowback
Weight: 4.5kg
Overall length: 1023 mm
Barrel length: 450 mm (315 mm on G3KA4 model)
Magazine capacity: 20 rounds

G3A4 – retractable butt version of the G3

During the early- to mid-1950s West Germany, like the other NATO countries, faced the need for rearming its army for the newest common 7.62x51mm NATO caliber small arms. Initially Germans preferred the Belgian FN FAL rifle, and adopted it circa 1956 under the designation of G1. Due to obvious reasons Germany wanted to manufacture its military rifles, and attempted to buy a manufacturing license for FAL, but Belgium rejected the deal. So, Germany turned to the another design, available from Spanish company CETME, and known as the CETME mod. A rifle. Germany bought the manufacturing license for CETME rifle and transferred it to the Heckler und Koch (HK) company, located in Oberndorf. HK slightly modified the CETME design, and in 1959 the Bundeswehr (W.Germany Army) finally adopted the CETME / Heckler – Koch rifle as G3 (Gewehr 3 – Rifle, [model] 3). Since that time and until the 1995 the G3 in various modifications served as a general issue shoulder weapon not only for German Armed forces, but also for many other countries. Those include Greece, Iran, Mexico, Norway, Pakistan, Portugal, Sweden, Turkey and many other countries. Total of more than 50 countries during the last 40 years issued the G3 to its forces. The G3 was or still is manufactured in countries like the Greece, Pakistan, Iran, Turkey, Portugal and others. The key reason of high popularity of the G3 is that it is much simpler and cheaper to manufacture, than its major contemporary rivals – Belgian FN FAL and US M14. To the best of my knowledge, the HK itself continued to produce and offer the G3 until the year 2000 or 2001, when it finally disappeared from HK catalogs and web-sites. However, the HK still manufactures a wide variety of firearms, based on the G3 design but of different purposes and calibers, like 9mm MP-5 submachine guns, 5.56mm HK 33 assault rifles, 5.56mm and 7.62mm HK 23 and HK 21 machine guns, PSG1 sniper rifles etc. In general, the HK G3 rifle can be described as one of the best 7.62mm NATO battle / assault rifles – reliable, versatile, controllable, non-expensive and, finally, very popular. For the civilian markets, HK produced the semi-automatic only versions of the G3, initially known as HK 41 and later – as HK 91.

G3A3 with drum type rear sight, plastic ventilated handguards and fixed stock

The G3 rifle is a selective fire, magazine fed rifle, built using delayed blowback action, developed by German engineers at Mauser Werke late in the 2nd World War and refined in Spain, at the CETME company. Initial models of the G3 rifle were quite similar to CETME rifles, and even had “CETME” markings on the receivers (until 1961 or so). The roller-delayed blowback action is described under the CETME Rifles, so I will not repeat it here. The G3 is built using as many stamped parts as possible. The receiver is stamped from sheet steel. The trigger unit housing along with pistol handle frame, also are stamped from steel and hinged to the receiver using the cross-pin in the front of the trigger unit, just behind the magazine housing. Earliest G3 rifles also featured stamped handguards and CETME-type flip-up rear diopter sights. In the mid-1960s the initial design was upgraded to the G3A3 and G3A4 configurations. These rifles had ventilated plastic handguards and a drum-type rear diopter sights, marked from 100 to 400 meters. The G3A3 was a fixed butt version, with buttstock made from plastic, and the G3A4 was a telescope butt version, with retractable metallic buttstock with rubber buttplate. Late German production G3A3 and G3A4 models were built using new trigger units, integral with restyled pistol grip and triggerguard, made from plastic. The shortest version of the G3 was the G3KA4, similar to G3A4 but with shortened barrel. Every G3 rifle can be equipped with detachable bipods, claw-type detachable scope mounts. Long-barreled versions can be fitted with bayonet or used to launch rifle grenades from the barrel. Folding cocking handle is located on the special tube above the barrel, at the left side, and does not reciprocate when gun is fired. The safety / fire selector is located above the triggerguard on the left side of the trigger group housing and usually is marked “S – E – F” (Safe – Single shots – Full auto). Latest models could have selectors marked with colored icons.

Caliber: 5.56x45mm NATO
Action: Gas operated, rotating bolt
Overall length (stock collapsed/extended): 10″ barrel: 686 / 785 mm; 14″ barrel:
Barrel lengths: 10.5″ / 267mm; 14.5″ / 368mm; 16.5″ / 419mm and 20″ / 508mm
Weight: 3.31 kg w. 10.5″ barrel, 3.5kg w 14.5″ barrel
Rate of fire: 700-900 rounds per minute
Magazine capacity: 30 rounds

Following the revision of the OICW Block 1 / XM8 program, the Heckler & Koch company decided to enter the US military and law enforcement markets with the alternative design, which, in fact, looks quite promising. Based on the experience, gained during successful upgrade program of the British SA80 / L85A1 program, HK decided to cure the existing M16 rifles and  M4 carbines from most of their problems, inherent to this 40-years old design. The key improvements, made by HK, are their patented short-stroke gas piston system, borrowed from HK G36 rifle. This system replaced the direct gas system of standard M16 rifle, so no powder residue will remain in the receiver even after long shooting sessions. The “new” gas system also is self-regulating and will work reliably with any barrel length. Other improvements include new buffer assembly, improved bolt, and a cold hammer forged barrel, as well as free-floating handguard with integral Picatinny-type rails. Originally developed as a “drop-in” upper receiver assembly for any standard M16/M4 type lower receiver, HK416 is also available as a complete weapon, with HK-made lower receivers. Current (late 2005) models include carbines with 10.5″ and 14.5″ barrels, and 16.5″ barreled carbine and 20″ barreled rifle will be added later.

Another interesting development, which is apparently based on the upscaled HK416 design, is the HK417 – the 7.62x51NATO rifle that combines AR-15/M16 type ergonomics, layout and handling with improved reliability of HK-made and designed gas piston system. This rifle probably will use HK G3-type magazines. If the rumors about HK417 are true, the 5.56mm HK416 / 7.62mm HK417 combination will be a direct rival to the newest FN SCAR system.

HK416 is a gas operated, selective fired weapon of modular design. It uses short-stroke gas piston that operates the 7-lug rotating bolt. Receiver is made from high grade aluminium alloy. Combination-type safety / fire selector allows for single shots and full automatic mode. Hk416 retains all M16-style controls, including last round bolt hold-open device, rear-based charging handle and magazine release button on the right side of the magazine well. HK416 is fitted with four Picatinny rails as standard, and may accept any type of sighting devices on STANAG-1913 compliant mounts. It also can accept modified HK AG36/AG-C 40mm grenade launcher, which is clamped directly to bottom rail. Buttstock is of typical M4 design, multi-position telescoped.