Zastava M76 - Design Details

Design Details

The M76 is similar in concept to the Russian Dragunov SVD sniper rifle; a semi-automatic rifle using a full-power cartridge from a 10-round magazine. However, the M76 is closer to the AK-47 design than the Dragunov, similar to the Romanian PSL. Being derived from the AK design it is simple and reliable, and like other Zastava AK-derivatives it is of high-quality manufacture. Accuracy is typically around 1.5 MOA, which is good for a Kalashnikov design and entirely acceptable for the designated marksman role.

Rather than being a Dragunov clone, it looks more like a lengthened AK-47 with a heavier barrel, an impression strengthened by the separate stock and pistol grip rather than the Dragunov's thumbhole combination stock. Instead of the Dragunov's 7,62x54mmR chambering it uses the 7.92x57mm Mauser a.K.a. the 7.9mm or 8x57mm IS round. The Yugoslav National Army (JNA) adopted a 7.9mm Cartridge, Ball M49 variant, designated as M49, as infantry ammunition at the end of the 1940s and later a 7.9mm Cartridge, Sniper, with Universal ball M75, as sniper ammunition, designated as M75. Instead of the Dragunov's separate gas piston, the M76 has an AK-type piston attached to the bolt carrier. The receiver is a milled forging like that of the original AK-47 to give greater rigidity when firing a full-power round and it is longer to suit the 8x57mm IS chambering. The AK-type rotating bolt, bolt carrier, barrel and other parts are also longer and heavier to suit. Feeding is via a 10-round steel box magazine, which has a follower that holds the bolt open after the last shot. Since there is no device in the weapon to hold the bolt to the rear, the bolt will move forward when the magazine is removed, which increases the difficulty of removing the magazine. Fire is semi-automatic only, so the AK-47-type safety on the right side of the receiver has only 2 settings - 'safe' and 'fire'. The barrel has a tapered profile with a Dragunov-type combination slotted flash suppressor and foresight housing. A standard AKM bayonet can be fitted to the bayonet lug below the foresight. Like the Dragunov, but unlike the AK-47, the M76 features an operator-adjustable gas regulator enabling more propellant gas to be vented to the piston in marginal operating conditions and even blocking the gas from pushing back the bolt, making the rifle bolt action.

The furniture features a straight comb butt, which has a rubber pad similar to that found on the Zastava M70 series of weapons, and a well-shaped contoured pistol grip. The fore-end is also reminiscent of that found on the M70 series. There is no butt trap for cleaning kit storage in the wooden butt. In newer production models the wooden furniture is replaced with synthetic polymer material which offers some storage space for accessories like a cleaning kit and reduces the M76 overall weight by approximately 0.5 kg.

With the exception of the gas regulator, disassembly and operation are similar to that of the AK-47/AKM family of weapons.

Though the M76 fires its bullets at a relatively modest 730 m/s (2395 ft/s) muzzle velocity, the 8x57mm IS cartridge loaded with aerodynamically efficient 12.8 gram (198 gr) military sS ball bullets still offers a supersonic reach of ≈ 910 m (995 yd) under ICAO Standard Atmosphere conditions at sea level (air density ρ = 1.225 kg/m³).

To mount the optics, a side-rail is permanently attached to the left wall of the receiver which accepts an alloy sliding dovetail mount with a clamping lever to which can be attached various telescopic sights and night optics. The mount is detachable from the receiver rail in seconds by swinging the locking lever open and sliding the scope and mount off the rail to the rear. It can be removed and reattached without loss of zero. The optic sight is normally removed during field stripping to give easy access to the receiver cover and bolt carrier. The rifle features mechanically adjustable backup AKM-type iron sights with a sliding tangent rear sight which can be adjusted from 100 m to 1,000 m. These sights can be used with or without the optic sight in place.

The typical scope used is a ZRAK ON-M76 4x 5°10’ scope originally produced in the ZRAK factory in Sarajevo, Bosnia and Herzegovina. This optical sight is similar to the PSO-1 4x24 sight used on the Russian SVD rifle and the Romanian I.O.R. LPS 4x6° TIP2 4x24 sight used on the PSL rifle. The ON-M76 elevation turret features bullet drop compensation (BDC) in 50 m increments for engaging point and area targets at ranges from 100 m up to 1,000 m. The BDC feature must be tuned at the factory for the particular ballistic trajectory of a particular combination of rifle and cartridge (the 7,9 M76 ball round) at a predefined air density. Inevitable BDC induced errors will occur if the environmental and meteorological circumstances deviate from the circumstances the BDC was calibrated for. Marksmen can be trained to compensate for these errors. Besides the BDC elevation or vertical adjustment control of the reticle, the windage or horizontal adjustment control of the reticle can also be easily dialed in by the user without having to remove turret caps etc. The reticle illumination of the ZRAK M-76 4x 5°10’ is provided by (radioactive) tritium. The tritium light source has to be replaced every 8–12 years, since it gradually loses its brightness due to radioactive decay. The reticle features a PSO-1 type range-finding reticle.