|
In 1960s the US Army adopted a new round, caliber 5.56x45 mm. Considering
this a serious challenge, the Soviets could not but react accordingly. A
novel round of 5.45x39 mm was supposed to be an antipode to the American
5.56 cartridge.
In 1965 - 1966 TSNII TOCHMASH, Russian leading institution in small arms
research, outlined new principles of enhancing effectiveness of automatic
weapons by means of the so-called balanced automatics. Preliminary
experiments revealed that the experimental low-impulse cartridge in caliber
5.45x39 mm round might be a perfect challenge to the 7.62x39 mm, model
1943, unitarian intermediate round. Army experts believed that the new
"weapon + round" complex would pave the way toward a new generation of
infantry small arms.
The then Soviet military wanted to create a weapon, which would be lighter
but more effective than the issue
AK47,
thus making assault rifles in their
classical notion outdated and absolete conceptually.
A contest was declared. Izhmash and the Kovrov Arsenal accepted the
challenge.
Izhmash commissioned
Youriy Alexandrov, a young and promising arms designer.
|
AL-4 was developed in 1960s.
Barrel and bolt were later derived for
the AK74.
|
|
He was appointed as a project engineer to do the job. The Kovrov design
bureau had Alexander Konstantinov as a participant of the contest.
The army wanted to have the weapon as simple and as reliable as the AK47
assault rifle, but with substantially better performance capabilities,
accuracy in particular. For this reason, they recommended that AKM be taken
as a basic model for this experiment. Izhmash made an attempt to not only
adapt the well-fielded firearm to the new ammunition but also to improve its
construction by creating a mechanism of decreasing the muzzle jump, by
substantially enhancing controllability and hit probability of the weapon.
Youriy Alexandrov created a series of experimental rifles, two of them being
AL- 4 and AL-7.
AL-4 (Avtomat Lehkiy stands for "light assault rifle") turned out a serious
and a tough competition. This version had a laminated handguard, a
non-folding buttstock, and an orange plastic 30-rd detachable
magazine, like
the AKM assault rifle. Alexandrov says, his basic weapon was designed in
1969. Experimental and research works, however, were still going on for a
few years more. Finally, the weapon successfully passed all tests, and the
project was completed by May 22, 1972. A later version - AL-7 - had a
|
AL-7 is another step toward AK74.
|
|
typically
AK74M furniture: a folding buttstock made from the black
glassfibre-reinforced polyamide. A pistol grip, magazine and handguard were
also derived from the AK74M rifle. In contrast to the AK weapons, both AL-4
and AL-7 had a stamped steel top cover with transverse semi-circular ribs,
and with the rear sight attached to the front tip of the cover.
At that period Mikhail Kalashnikov
and his team were about to complete
modernization of the AKM assault rifle, adapting it to the 5.45x39 mm
cartridge. "To be or not to be" - which of the weapons, AL-7 or
AK-74, would
get the upper hand with the military, was a tough question.
The results of an extensive experimentation revealed that the technical
doctrine of the balanced automatic mechanics would require substantial
capital investments for the factories to change their production lines. The
ailing Soviet economy could not afford such a heavy financial burden.
Further financing of the program became a problem.
Finally, developments and research on the AK-type small arms lead to a
compromise between the economic factors and the effectiveness of the weapon.
Thus the AK-74 and its modifications were accepted for service.
In the late 1970s and 1980s the
ABAKAN program got everybody's attention.
This contest resulted in creation of the futuristic "leap-ahead" AN-94
assault rifle, and the idea of the balanced automatics was abandoned. But
only temporarily.
|
AL-7: field-stripped.
|
|
Taking into account that labor content of
AN-94 is 4 to 5 times greater than
that of AK-74M,
its market price is higher accordingly. A reasonable
question: Is every customer ready to spend such money for an assault rifle?
In the global economical crisis that has been chasing the world for the last
several decades, made the AK rifles rather competitive. Most customers in
the traditionally "Russian" segments of the international arms market still
prefer an old and a well-known, well-proven system. What they really want,
is AK with better accuracy. The engineers at IZHMASH came to a conclusion
that such a weapon could be made by fitting a firing mechanism of AL-7 into
the body of AK-74M.
Youriy Alexandrov, Valeriy Paranin and their team did the job.
AK-107 is made in caliber 5.45 while AK-108 in caliber 5.56 NATO.
Designation
AK in this case stands for
Alexandrov + Kalashnikov.
SPECIFICATIONS
| | AK-107 | AK-108 |
|---|
|
Caliber: | 5.45 | 5.56
| | Cartridge: | 5.45x39 | 5.56x45
| | Operation: | Semiautomatic,
burst of 3
rounds and
full-auto fire modes.
Fire from the closed-bolt position.
| | Cyclic rate: | 850 to 900 rpm
| | Sighted range of fire: | 1,000 m
| | Feed: | Fiberglass-reinforced
polyamide 30-round
box-type detachable magazine.
| | Weight, empty without mag.: | 3.6 kg.
| | Weight of magazine, empty: | 0.20 kg.
| | Length, overall: | 943 mm
| | Length, with buttstock folded: | 695 mm
| | Barrel: | Four-grooves, with
right-hand
twist of one turn
in 200 mm (AK-107)
and 178 mm (AK-108).
| | Barrel length: | 415 mm.
| | Sights: | Sliding tangent-type rear
sight with U-notch.
Round, post-type front
sight with protective ears;
adjustable for windage and elevation zero.
| | Finish: | Black phosphate.
| | Furniture: | Black
fiberglass-reinforced
polyamide pistol grip.
| | Muzzle velocity: | 900 m/sec | 910 m/sec
| | Weight of round: | 10.2 g | 12.5 g
| | Weight of bullet: | 3.42 g | 4.5 g
|
CONSTRUCTION AND STANDARD OPERATIONS
As
|
AK107/AK108: synchronization unit, assembled..
|
|
seen from the photos, the AK-107 and AK-108 Assault Rifles have minor
cosmetic differences compared to standard AK100-series.
The top cover is fixed to the receiver by means of a lever on its rear end.
The geometry of case ejection opening looks slightly differently from the
one in the original AK weapons. The steel cover of gas chamber extends from
the top handguard to the front sight block.
The bolt, the construction of trigger mechanism, receiver, fire mode
selector, front sight, the stock, magazine and muzzle brake are identical
with the AK-family weapons.
The basic difference between AK-107/108 and original AK is the availability
of counter-balancing synchronizer with a six-tooth sprocket.
The AK-107/108 rifles consist of the following main parts and
components:
The principles of operation of the AK-107/108 weapons are based on the
utilization of energy of propellant combustion gases diverted from the
barrel into the gas chamber through the side opening in the barrel.
In order to reduce negative effect of the shock of bolt carrier in its
front and rear positions, the carrier features a connecting rod in the form
of a perforated lower rail. The latter is synchronized with the upper rail
by means of a six-tooth sprocket. When a round is fired and the gas escapes
into the gas cylinder to activate the two pistons of the upper rail and that
of bolt carrier, the bolt carrier rolls into its rear position while the
upper rail travels into its front position. The two dead points are reached
by two inertia masses simultaneously, thus reducing recoil shock thanks to
the synchronizing effect of the sprocket.
|
AK107, with accessories: bayonet, cleaning tools, cleaning rod and
oiler.
|
|
Length of travel of firing parts in AK-107/108 is shorter than that of the
AKM rifle - hence the time of cycle is shorter. This results in a greater
cyclic rate of fire. AK-107 and AK-108 are capable of firing 850 to 900
rounds per minute. When travelling rearwards, the bolt carrier turns the
bolt to open the barrel and pushes it also rearwards. The empty case is
extracted from the chamber and ejected through the right-side opening in the
top cover. While the carrier rushes towards the rear of receiver, the upper
rail comes forward and compresses its return spring. As soon as the two dead
points are synchronically reached, both the carrier and the upper rail begin
reciprocating motion under the influence of their return springs.
The bolt strips the next round from the magazine, rams it into chamber and
locks it in battery. The chamber locked, the bolt carrier disengages the
auto-sear from the firing notch of the hammer. At this same moment the upper
rail moves rearwards. The two pistons arrive into both ports of gas chamber.
Fire mode selector in its upper position inerts the weapon and brings it
into safety.
If the selector is placed into position marked "A" (avtomatichskiy -
automatic mode of fire) and the trigger is continuously depressed, the
weapon depressed, the weapon keeps on firing to the last round in the
magazine.
|
AK108: top (receievr) cover is attached with lever.
|
|
When the selector comes one step below into position marked "3", the rifle
fires 3-round bursts. This possibility is provided by the special
ratchet-and-paw device available on the selector axle. The ratchet has three
teeth. When so placed, the rifle fires three successive shots, while the
bolt carrier interacts with the ratchet. Each time the bolt approaches and
pushes the device, the latter is turned to the value of the tooth's module
and retained in such position. As soon as the last of the three rounds is
fired and the ratchet comes into extreme rear, it is automatically released
to resume its initial position. The sear retains the hammer. The round is
locked in the barrel. To resume the next 3-round cycle, the trigger should
be released and depressed again. The hammer releases from the sear to rush
forward and strike upon the firing pin. The first shot of the next 3-round
burst is delivered.
If the selector is in the extreme lower position marked "1" (single fire,
semiautomatic mode) and the trigger is depressed, the weapon delivers only
one shot. In order to repeat the cycle, the operator has to repeatedly
release and depress the trigger.
The author found that the average accuracy (fire in a standing position
without support) of both AK-107 and AK-108 is by 1.5 - 2.0 times better than
that of standard AK100-series firing similar types of ammunition.
TOP
|
