Monday, June 4, 2007

PSG-1

The Guys in the Police and Counter-Terrorism, rely on the best semi-automatic sniper rifle off the shelf. Presenting.... Heckler and Koch's PSG-1.


Caliber: 7.62 x 51mm NATO (.308 Win)
Action: Semi-automatic, roller-delayed blowback
Barrel: 650 mm
Overall length: 1208 mm
Weight: 8.10 kg with scope and no magazine
Magazine: 5 or 20 round detachable box
Scope: Hendsoldt 6x42, 6 settings from 100 to 600 meters
Expected accuracy: Sub-1MOA with match grade ammunition

The PSG-1 sniper system (PrazisionsSchutzenGewehr, or "high-precision marksman's rifle" in English) had been developed by the German company Heckler - Koch by the mid-1980s as an ultimate police and counter-terror weapon. Some German elite law-enforcement groups, like GSG or KSK-9, participate in this development, and since its introduction the PSG-1 had been adopted by various police forces in Europe and Americas. It is way too heavy and somewhat too gentle for military use, so it never seen any military use. Instead, HK developed two more sniper weapons. The first, that actually preceded the PSG-1, was the G3-SG1, an accurized and scope-fitted version of the basic G3 automatic rifle for German Army. And in the mid-1980s HK also developed a derivative of the PSG-1, called MSG-90, for export military sales. The PSG-1 is still offered by the HK, and is one of the most expensive factory-made sniper rifles on the market, hitting the $10.000 price tag in the basic package.

Technically, the PSG-1 is no more than a heavily modified G3 rifle. It features the same roller-delayed blowback action, derived from earlier CETME rifles, and the same stamped steel receiver with separate detachable trigger unit. The heavy barrel is precisely made by the cold hammer forging process with polygonal rifling for improved accuracy and longer life. Special trigger unit features a semi-automatic only hammer group and the adjustable trigger with trigger pull of about 1.5 kg (3 lbs). The ergonomically shaped pistol grip features an adjustable palm stop. Plastic buttstock is also adjustable for height and for length of pull. Another non-typical feature of the PSG-1 is the "silent bolt closing device", actually similar to the forward assist, found on M16 rifles. This is apparently to be used in situations where a complete silence must be maintained until the shot is fired. The devise is no more that a pushbutton, located just behind the ejection port, and linked to the bolt carrier by the ratchet-like device. The rifle is fed using standard 20-rounds G3 magazines or special 5-rounds magazines. There's no open (iron) sights on the PSG-1. Instead, it is fitted with the Hendsoldt 6X42 fixed power telescope sight with illuminated reticle. The scope has built-in range adjuster that works in ranges from 100 to 60 meters, so 600 meters is considered the maximum effective range. Most strangely, the PSG-1 had no integral bipod. Instead, it is often used with the separate rest, mounted on the compact tripod.

BAR M1918 (Browning Automatic Rifle)

"1st squad draw their fire to their left, second squad, give a full supressing fire on them"
Supressing fire is the word for use for a BAR MG.

Data for M1918A2
Caliber:
7.62x63mm (.30-06 M2)
Weight: 8.8 kg empty
Length: 1214 mm
Length of barrel: 610 mm
Feeding: detachable box magazine, 20 rounds
Rate of fire: 450 or 650 rounds/min, selectable

The Browning Automatic Rifle was designed by the famous American arms designer John Moses Browning late in the First World War, on the request from US Expeditionary corps in Europe. Initially it was just like that - the Automatic Rifle, a selective fire weapon, intended for use by infantry men to fire from the shoulder or from the hip when advancing onto the enemy positions, and to provide mobile firepower to every squad, since the standard machine guns were heavy and much less maneuverable. But the BAR M1918 was way too heavy for a shoulder fired weapon, being more that 2 times heavier than a bolt-action Springfield M1903 rifle and exactly 2 times heavier than a latter M1 Garand semiautomatic rifle. On the other hand, it was too light to be controllable in full automatic mode, especially when firing such a powerful round from a shouldered unsupported position. Anyway, the M1918, made by the Colt Firearms co. were issued to some US troops by the end of the war. After the war, the development of the BAR continued. In 1922, US Cavalry adopted the M1922 light machine gun, which featured a folding bipod under the partially ribbed barrel, a removable monopod ("third leg") under the butt, and a M1917 machine gun sights. The Colt company also produced a lightened semi-automatic version of the BAR, called a Colt model 75 "Monitor" rifle. This was intended mostly for police use, but also found its way into the hands of outlaws, too.

During the 1930s, next version of the BAR, designated as M1918A1, was briefly manufactured. This gun featured skid-footed folding bipods, attached to the gas block. The butt was fitted with hinged steel buttplate.

In 1939, the final American version of the BAR appeared, under the designation of M1918A2. This version, manufactured by Colt, Marlin-Rockwell, and Winchester, served in the Squad Automatic Weapon role with US troops during the 2nd World War and latter Korea War. Many of earlier M1918A1 guns were converted to the M1918A2 configuration, which featured skid-footed adjustable bipod under the flash hider, M1917 sights, smaller forend and metal heat shield between barrel and cylinder/spring, single shots replaced by two selectable full auto modes, with fast (~650 rpm) and slow (~450 rpm) rates of fire. The bipod, however, was somewhat awkward, uncomfortable and heavy, so many M1918A2 were used with bipod removed.

The BAR also found its way into many European armies, when Browning sold his design to the famous Belgian company Fabrique Nationale. In more or less modified form, BAR served with Poland, Sweden, Belgium, Baltic states and so on. The ultimate BAR version, however, appeared only after the 2nd World War, when FN introduced its BAR Type D light machine gun, with quick detachable barrel and return spring moved into the butt. This gun had seen not too much service, being adopted only by Belgian army prior to switch to the smaller 7.62mm NATO cartridge. There were numerous attempts in the USA to convert the BAR for this new ammunition, but the design was poorly suited to modern manufacturing, so with the adoption of the 7.62x51mm NATO as a standard ammunition the US army was left without its Squad Automatic weapons until the 1982, when the M249 SAW (FN Minimi light machine gun) was introduced into service.

It must be noted that while being technically a very good design (typical for Browning's genius), BAR was not too successful in both Automatic Rifle and LMG role. For Automatic Rifle it was too heavy and too uncontrollable in full auto. For LMG, it lacked the magazine capacity and the quick replaceable barrel, being inferior in terms of sustained firepower to the pre-WW2 LMGs like British BREN, Soviet Degtyarov DP-27 and the like.

Technical description.
The BAR M1918 is a gas operated, magazine fed, air cooled weapon. It used the gas piston, located under the barrel, and the bolt with tilting locking lug, that was raised to lock into the roof of the receiver. This lug was linked to the operating rod via the swinging link, much like in the earlier Berthier system. The BAR always fired from the open bolt to avoid cook-offs. The return spring was located around the gas piston under the barrel, so it was prone to overheating and lost its temper during the prolonged fire sessions, resulting in jams and stoppages. This issue was somewhat cured in M1918A1 with introduction of the heat shield between the barrel and the spring, located inside the forend.

The receiver was a machined piece of steel, and the un was fed from the detachable 20 rounds box magazines. Barrel was fitted with flash hiders of different types, and, since the M1818A1, the wooden buttstock was also fitted with the hinged buttplate. The latter production models of M1918A2 were also fitted with carrying handle.

The buttstocks and forends were mostly made from wood, but on late production M1918A2's sometimes were also made from plastics.

Ak-47

Russian counterpart for the M4 Carbine.

Caliber 7.62x39 mm
Action: Gas operated, rotating bolt with 2 lugs
Overall length: 870 mm
Barrel length: 415 mm
Weight, with empty magazine: AK 4,3 kg; AKM 3,14 kg
Magazine capacity 30 rounds (40 rounds box magazines and 75 rounds drums from RPK also may be used)
Cyclic rate of fire 600 rounds per minute
Maximum effective range: about 400 meters