FN FAL
Fusil Automatique Léger
FN Herstal1953–1988Early Cold War
Also known as L1A1 SLR, Right Arm of the Free World
Image credit
- Title
- File:Century Arms FN FAL.jpg
- Author
- Snark(attribution required)
- Licence
- CC BY-SA 3.0
- Source
- https://commons.wikimedia.org/wiki/File:Century_Arms_FN_FAL.jpg
How Muzzle energy is calculated
E = ½ · m · v²
Inputs
- m9.525 g147.0 grverifiedsourcePublished as 147 gr; 1 gr = 0.06479891 g exactly.
- v853 m/s2,799 fpsverifiedMeasured with a 558.8 mm barrel, not this arm's 533 mm. Velocity outside the sourced range is not projected.
1 of 2 inputs link to their source.
How Muzzle velocity is calculated
nearest sourced barrel length, no extrapolation
Inputs
- v at 558.8 mm853 m/s2,799 fpsverifiedsourceBallistics table of the cited article.
Assumptions
- This figure belongs to a 558.8 mm barrel. It is shown because it is the closest measurement that exists, not because it applies here.
1 of 1 inputs link to their source.
How Loaded mass is calculated
m_loaded = m_empty + m_magazine + n · m_cartridge
Not calculated: m_magazine has no sourced figure yet. Nothing is substituted for a missing input.
Assumptions
- One magazine, filled to the stated capacity. Spare magazines, optics, slings and lights are the owner’s, not the arm’s.
2 of 4 inputs link to their source.
How Free recoil is calculated
E_recoil = ½ · m_firearm · v_recoil²
Inputs
- m_firearm4.25 kg9.370 lbverifiedsource
- v_recoil1.912 m/s6.272 fpsestimated
Assumptions
- Propellant gas momentum is excluded: ARMAG does not record charge weights. This is therefore a lower bound on the real free recoil, consistent between entries but smaller than a figure that includes the gas term.
- Free recoil: the arm is unrestrained. Stock design, muzzle devices, stance and shooter mass are not modelled, because none of them is a property of the arm.
1 of 2 inputs link to their source.
How Capacity is calculated
as published for the primary chambering
Inputs
- capacity20verifiedsourceDetachable box magazines of 20 and 30 rounds; a 50-round drum exists.
1 of 1 inputs link to their source.
Derived figures
Computed from the sourced values above. Open ƒ on any figure for the formula, its inputs, and the assumptions it makes.
How Momentum is calculated
p = m · v
Inputs
- m9.525 g147.0 grverifiedsourcePublished as 147 gr; 1 gr = 0.06479891 g exactly.
- v853 m/s2,799 fpsverifiedMeasured with a 558.8 mm barrel, not this arm's 533 mm. Velocity outside the sourced range is not projected.
1 of 2 inputs link to their source.
How Sectional density is calculated
SD = mass(gr) / (7000 · diameter(in)²)
Inputs
- mass9.525 g147.0 grverifiedsourcePublished as 147 gr; 1 gr = 0.06479891 g exactly.
- diameter7.85 mm0.3091 inestimatedsourceNo free dimensional standard publishes the NATO round under that name. Borrowed from the C.I.P. datasheet for the commercial .308 Winchester (G1), which shares the chamber; the two are not interchangeable at the pressure limit.
Assumptions
- Reported in the conventional lb/in² so it is directly comparable with published figures.
2 of 2 inputs link to their source.
How Power factor is calculated
PF = mass(gr) · velocity(fps) / 1000
Inputs
- mass9.525 g147.0 grverifiedsourcePublished as 147 gr; 1 gr = 0.06479891 g exactly.
- velocity853 m/s2,799 fpsverifiedMeasured with a 558.8 mm barrel, not this arm's 533 mm. Velocity outside the sourced range is not projected.
Assumptions
- A competition classification defined by the IPSC and USPSA rulebooks, stated in their units. It describes a scoring category, not an effect.
1 of 2 inputs link to their source.
How Magazine dump is calculated
t = (n − 1) / (rpm / 60)
Inputs
- n20verifiedsourceDetachable box magazines of 20 and 30 rounds; a 50-round drum exists.
- rpm675 rpmestimatedsourceThe article publishes 650–700 rounds/min. Recorded as the midpoint of that range.
Assumptions
- Cyclic rate held for the whole magazine, no stoppages, trigger held down. A theoretical figure for comparing mechanisms, not a measured one.
2 of 2 inputs link to their source.
How Sight error at 1 mm is calculated
θ = atan(misalignment / sight radius)
Not calculated: sight radius has no sourced figure yet. Nothing is substituted for a missing input.
Assumptions
- Shows what a stated aiming error costs. The misalignment is the reader’s figure; the site does not claim how well anyone aims.
No input on this calculation carries a clickable source yet.
Specifications
Every row here is generated from the schema, so a figure recorded on this entry cannot be missing from the table, and the same rows, read the same way, are what the comparison shows.
Identity
- Type
- Rifle
- Action
- Self-loading
- Fire modes
- Semi-automatic
- Fully automatic
- Operating system
- Gas, short-stroke piston
- Designed in
- Belgium
- Introduced
- 1953
- Production
- 1953–1988
Dimensions and mass
Sights and rifling
- Sight radius
- not recorded
- Sight height over bore
- not recorded
- Rifling twist
- not recorded
- Twist direction
- not recorded
- Grooves
- not recorded
- Sight graduation
- 600 m656.2 ydsource
Ramped aperture rear sight, adjustable from 200 m in 100 m increments.
Chamberings
- 7.62×51mm NATOprimary20 rounds
Scale
A to-scale outline against family siblings. The dimensions are sourced; the shape is a representative outline for the type, and says so.
- FN FAL1,090 mm42.91 inheight not recorded
Representative outline: the dimensions are sourced, the shape is not. Overall length, and barrel length where recorded, are drawn from this entry's own figures; the profile is a generic one for the firearm type and says nothing about this arm's actual contours. FN FAL records no height, so its outline is drawn at the type's proportion. That height is part of the shape, not a measurement.
Detail
Dieudonné Saive designed it for the .280 British intermediate cartridge and was made to rebuild it around the 7.62×51mm after the United States refused to standardise on anything smaller. That decision is the central fact about this rifle: everything awkward about it (the recoil in automatic fire, the length, the 4.25 kg) follows from a cartridge its designer did not choose.
The mechanism is a short-stroke gas piston driving a breechblock that tilts downwards into a shoulder in the receiver floor, and it is unusually adjustable: a gas regulator with a graduated collar lets the rifle be tuned to ammunition or to a fouled action, which is a large part of why it worked in ninety countries.
Most of those countries issued it semi-automatic only, having reached the same conclusion the Americans did about a nine-and-a-half-pound rifle firing a full-power cartridge on automatic. The British L1A1 removed the capability entirely.
Its nickname came from the map: at the height of the Cold War it was the standard rifle of most of NATO and much of the non-aligned world, while the other side carried Kalashnikovs.
References
This entry's own bibliography. Every citation key on this page resolves into this list.
- FN FAL · Wikipedia · 1369793805 · read 2026-08-31 · CC BY-SA 4.0
Last verified 2026-08-31 · review status: agent-populated