FN Evolys: A New Ultralight Squad Automatic Weapon in 5.56mm & 7.62mm

Overview

This video provides a hands-on look at FN’s new ultralight belt-fed machine gun, the FN Evolys, offered in:

• 5.56×45mm NATO
• 7.62×51mm NATO

Ian McCollum emphasizes that the Evolys is not intended as a direct replacement for FN’s existing Minimi or FN MAG. Instead, FN designed it as a middle-role utility gun positioned between:

• a rifle/ammunition bearer concept, and
• a true heavy “full-capability” light machine gun.

The design goal is maximum firepower with minimum weight, aimed especially at special-operations suitability: fast movement and strong suppressor/optic compatibility, without the weight and heat/logistics burden typical of traditional systems.

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Why FN built it (2015 concept origin)

Around 2015, FN received two competing user demands:

1. Some units wanted a rifle-like infantry automatic weapon with more sustained fire (conceptually similar to the M27 IAR/BAR family).
2. Others wanted a Minimi-like machine gun but substantially lighter.

FN concluded that these demands justified designing the Evolys from the ground up.

Key departure: belt-fed, no quick-change barrel

The Evolys is belt-fed for both calibers and, notably, does not use a quick-change barrel. The rationale presented is that many units carry only limited ammunition (often ~600–1,000 rounds) and may not carry spare barrels—meaning quick-change barrels often aren’t used the way the concept assumes.

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Weight and role positioning

Empty weight targets highlighted in the video are:

• ~12 lb (5.6 kg) for the 5.56 version
• ~14.9 lb (6.3 kg) for the 7.62 version

The speaker argues this makes it far lighter than most 7.62 NATO machine guns.

The gun is also framed as optimized for:

• suppressed operation
• modern accessories such as clip-on optics and night vision/thermal
• staying “handy” enough for rapid movement

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Design for accuracy with modern optics

A major modernization theme is keeping optics stable without requiring the gun to be opened/shifted during loading/clearing.

Fixed rail with feed access relocated

• The Evolys uses a fixed, full-length Picatinny rail (instead of a movable top cover).
• FN provides feed access by relocating the feed cover to the side at 45°, allowing the belt to feed upward at an angle while the receiver top stays solid.

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Manufacturing and internal engineering highlights

Receiver

• The receiver is described as a single aluminum casting using a lost-wax process, supported by cooling holes and internal structural design.

Feed component

• A complex feed part is said to be produced via additive manufacturing in mass production, with layers oriented for strength (not just for prototyping).

Barrel changes

While it’s not “quick-change,” FN describes the barrel as “easily changeable”:

• Remove one screw (aimed at armorer-level replacement rather than field swaps).

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Gas system and suppressor compatibility

• The Evolys uses a short-stroke piston approach.
• It includes only one gas port setting, based on FN testing that concluded it is reliable enough to avoid needing an adverse/adjustable setting.
• It is also designed around modern flow-through suppressors, with FN claiming it generally doesn’t need reduced suppressor settings—targeting simpler handling and maintenance.

Gas plug retention detail

• The gas plug has one shooting detent and another larger notch to help free it if fouled.

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Belt feed behavior and handling

• The feed tray tilts at 45°.
• The video notes that despite the angle suggesting rounds could slide, retention pawls prevent that behavior.

Loading and self-correction behavior

• Belt links are loaded by snapping them into place.
• A key point shown is that if ammunition is mis-seated during loading, the system’s closing feed cover/controls can self-correct into firing condition, with an emergency behavior described.

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Fire control and operating feel

Open-bolt operation and selector

• The gun fires from an open bolt.
• It has safe / semi / fully automatic selection, with an ambidextrous selector.

Semi-auto use case

• Semi-auto is highlighted as useful for zeroing and downrange presentation, with the gun described as feeling rifle-like.

On-camera shooting impressions

• 5.56 version: described as very soft shooting on a bipod (consistent with its mass and caliber).
• 7.62 version: also described as soft, with a smoother recoil impulse—less “sharp recoil,” more influenced by larger moving-mass dynamics.

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Bolt carrier, suppressor reliability, and buffer system

Bolt mechanism

• The bolt is described as a two-lug rotating bolt.

Suppressed-use geometry

• Cam/track geometry is modified for suppressor operation, including lengthening the cam track / dwell timing so the bolt avoids traveling into areas vulnerable to suppressor backpressure timing effects.

Hydraulic buffer

A major feature is a hydraulic buffer:

• Without the buffer: ~850 rpm
• With the buffer installed: ~750 rpm

The buffer is described as absorbing energy primarily from return travel (not acting like a spring that changes forward return force).

The narrator expresses skepticism about hydraulic buffer failure risk, but notes FN required significant development work to achieve acceptable durability. Earlier buffers apparently had higher failure rates and were introduced later.

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Disassembly and maintenance claims

The Evolys is presented as remarkably easy to disassemble/field strip, using steps such as:

1. Open the feed tray (ensure parts are forward)
2. Remove a main pin
3. Pivot stock, remove recoil spring
4. Pull reciprocating parts
5. Remove the fire control group via bottom panel steps

It is framed as maintenance-friendly without needing extensive field stripping.

Piston access

• Gas piston removal is compared to SCAR-style access, supported by receiver access holes.

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Presenters / contributors

• Ian McCollum (host; forgottenweapons.com)
• FN personnel at FN in Belgium (unnamed representatives involved in explanations and engineering discussion)