TFB Exclusive: Zastava M19 and M20 - Serbia’s New Assault Rifles

During my recent visit to Serbia, I had the remarkable opportunity to tour the Zastava Arms factory, located in the historic city of Kragujevac. Known for its long-standing tradition in firearms manufacturing, Zastava Arms has played a significant role in the region’s industrial and military history. Upon arrival, I was welcomed by members of the administrative staff, who provided a brief overview of the company's legacy, current production capabilities, and export operations.

Serbian Firearms @ TFB:

• Serbian AKs, Part 6: Morana, an Ambitious AK Upgrade Program
• Zastava M72: The RPK of Serbia is Finally in the U.S.! | SHOT 2025
• Zastava M21 – The New Generation Kalashnikov Rifle From Serbia That Never Caught On
• The Serbian RPK is Coming to the US: Zastava M72 LMG
• "The Sower of Death" - the History of Yugoslavian M84 Machinegun

Following our initial meeting, we proceeded to the shooting range, where I had the opportunity to closely examine some of the small arms produced at the facility. From classic models to the latest additions to their product line, each firearm reflects the precision engineering and craftsmanship for which Zastava is known. The visit included the unique opportunity to observe the test-firing of several weapons, offering a glimpse at the appreciation for their performance and handling.

In addition to the modern production facilities, we explored the Old Gun Foundry Museum, which shows Zastava’s deep historical roots dating back to the 19th century. The museum houses a fascinating collection of antique weapons, archival materials, and machinery that tell the story of the factory's evolution through periods of war, technological innovation, and regional transformation. The entire experience provided a deeper understanding of Serbia’s industrial heritage and the pivotal role Zastava Arms continues to play in the global arms industry.

Evolution of the Zastava Modular Combat System (MCS)

The development of the Zastava Modular Combat System (MCS) began around 2015–2016 as part of Project 1500, a comprehensive modernization initiative for the Serbian Armed Forces. One of the project’s key goals was to create a new generation of modular rifles in a new caliber, capable of meeting the diverse demands of modern combat.

The Zastava MCS was designed with modularity, caliber flexibility, and improved ergonomics in mind. Its construction allows for rapid barrel and component swaps, enabling soldiers, armorers, and maintainers to change barrels and calibers quickly and without the need for tools to adapt the weapon to various mission profiles. The platform supports two primary calibers: the well-established 7.62x39mm and the more advanced 6.5x39mm Grendel. Notably, both calibers use the same bolt, simplifying maintenance and logistics.

The 6.5mm Grendel stands out for its superior ballistic performance over both 7.62x39mm and 5.56x45mm NATO rounds. With improved aerodynamics, it offers a flatter trajectory, better velocity retention, and higher terminal energy, resulting in greater accuracy and lethality at extended ranges. However, this involves trade-offs: while the weight of the ammunition and the recoil are similar, the magazine capacities differ, with 30 rounds for 7.62x39mm and 25 rounds for 6.5mm Grendel. Dropping five rounds doesn't sound like a lot, but it represents a 16.67% reduction in magazine capacity and the ammunition loadout.

Zastava APM M19 Modular Assault Rifle

Developed in 2019 and unveiled around 2020, the Zastava APM M19 is the first fully developed and production-ready rifle from the MCS line. It is chambered in either 7.62x39mm or 6.5mm Grendel and features a 16.3-inch (415 mm) barrel, a gas-operated long-stroke system, and a rotating bolt. A non-reciprocating charging handle and tool-free barrel changes enhance operational flexibility. The M19 was officially adopted by the Serbian Armed Forces in 2022.

Based on the robust Kalashnikov design, the M19 incorporates elements from Zastava’s own M70/M72 platform, including the bulged front trunnion. A three-position gas regulator is integrated into each barrel-mounted gas block.

The rifle supports a full range of optics and accessories via a Picatinny top rail, reflecting a departure from traditional AK-pattern rifles displaying Zastava’s modern design philosophy.

Zastava AM M20 Compact Assault Rifle

The Zastava AM M20 is a compact carbine variant of the M19, optimized for close-quarters battle (CQB) and urban operations. Featuring a 10-inch (254 mm) barrel, the M20 retains full compatibility with MCS components, including caliber modularity and quick barrel changes.

Despite its shorter profile, the M20 delivers comparable performance, thanks to the reliable Kalashnikov-based internals and Zastava’s well-established production quality.

Both the M19 and M20 rifles reflect modern assault rifle design trends:

• Integrated receiver cover with a full-length Picatinny rail for optics and accessories.
• An ambidextrous charging handle is operable from either side and in upward or downward positions.
• Three-position fire selector: safe, semi-automatic, and fully automatic.
• Folding, telescopic stock with adjustable cheek rest.
• Ergonomic pistol grip and foregrip for hand stop for improved control.
• Chrome-lined barrel with a three-position gas regulator, marked according to caliber.
• Quick-change barrel mechanism, inspired by the PK/M84’s lateral locking wedge system, with adjustable headspace.

Besides ballistic performance, one of the biggest factors for an infantryman is weight, and the M19 comes in at 8.48 lbs. (3.85 kg), while the shorter M20 weighs 7.49 lbs. (3.40 kg). Shaving some weight from a few components could be beneficial; one example is the boxy gas block.

Conclusion

With over 160 years of experience, Zastava Arms is internationally recognized for its durable AK-pattern rifles, such as the M70. The development of the M19 and M20 rifles marks a significant shift in Zastava’s design philosophy, focusing on modularity, adaptability, and ergonomic advancement.

The Zastava M19 and M20 represent a major step forward for Serbian small arms manufacturing. By merging the rugged reliability of the Kalashnikov system with cutting-edge modular capabilities, Zastava has created a family of rifles well-suited for modern warfare. These platforms cater to domestic military needs and the demands of international clients seeking robust, adaptable, and high-performance weapon systems.

From the legacy of the M70 to the innovation of the MCS line, Zastava Arms continues to evolve, blending tradition with forward-looking design. Given the opportunity for further testing to evaluate the M19 and M20 rifles, I would take that opportunity, as it would provide valuable insights into their full operational potential.

Sources:

• Zastava Arms Military Product Catalogue
• Zastava Arms https://www.zastava-arms.rs/en/home/
• https://www.mod.gov.rs/eng/11806/odrzan-dinamicki-prikaz-dela-projekta-1500-11806
• https://www.mod.gov.rs/eng/16290/nova-modularna-puska-6-5-7-62-mm-u-naoruzanju-vojske-srbije-16290?utm_source=chatgpt.com
• https://www.zastava-arms.rs/en/2020/06/25/modular-combat-system-mcs-by-zastava-arms-serbia/