M1 carbine
Winchester Repeating Arms Company1942–1945Second World War
Also known as Carbine, Caliber .30, M1
Image credit
- Title
- File:M1 Carbine Mk I - USA - Armémuseum.jpg
- Author
- Armémuseum (The Swedish Army Museum)
- Licence
- Public domain
- Source
- https://commons.wikimedia.org/wiki/File:M1_Carbine_Mk_I_-_USA_-_Armémuseum.jpg
How Muzzle energy is calculated
E = ½ · m · v²
Inputs
- m7.128 g110.0 grverifiedsourcePublished as 110 gr; 1 gr = 0.06479891 g exactly.
- v579 m/s1,900 fpsverifiedMeasured with a 457.2 mm barrel, not this arm's 450.85 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 (SPEC.md §8.2)
Inputs
- v at 457.2 mm579 m/s1,900 fpsverifiedsourceBallistics table of the cited article, attributed to Army Basic Field Manual FM 23-7.
Assumptions
- This figure belongs to a 457.2 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_firearm2.359 kg5.201 lbverifiedsourcePublished as 5.2 lb; 1 lb = 0.45359237 kg exactly. Empty.
- v_recoil1.750 m/s5.740 fpsestimated
Assumptions
- Propellant gas momentum is excluded: ARMAG does not record charge weights (SPEC.md §14). 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
- capacity15verifiedsourceDetachable box magazines of 15 and 30 rounds.
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
- m7.128 g110.0 grverifiedsourcePublished as 110 gr; 1 gr = 0.06479891 g exactly.
- v579 m/s1,900 fpsverifiedMeasured with a 457.2 mm barrel, not this arm's 450.85 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
- mass7.128 g110.0 grverifiedsourcePublished as 110 gr; 1 gr = 0.06479891 g exactly.
- diameter7.85 mm0.3091 inverifiedsourceC.I.P. G1, maximum bullet diameter.
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
- mass7.128 g110.0 grverifiedsourcePublished as 110 gr; 1 gr = 0.06479891 g exactly.
- velocity579 m/s1,900 fpsverifiedMeasured with a 457.2 mm barrel, not this arm's 450.85 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)
Not calculated: rpm has no sourced figure yet. Nothing is substituted for a missing input.
Assumptions
- Cyclic rate held for the whole magazine, no stoppages, trigger held down. A theoretical figure for comparing mechanisms, not a measured one.
1 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
- Carbine
- Action
- Self-loading
- Fire modes
- Semi-automatic
- Operating system
- Gas, short-stroke piston
- Designed in
- United States
- Produced in
- Introduced
- 1942
- Production
- 1942–1945
Dimensions and mass
- Mass, empty
- 2.359 kg5.201 lbsource
Published as 5.2 lb; 1 lb = 0.45359237 kg exactly. Empty.
- Magazine, empty
- not recorded
- Length
- 904.2 mm35.60 insource
Published as 35.6 in; 1 in = 25.4 mm exactly.
- Length, folded
- not recorded
- Width
- not recorded
- Height
- not recorded
- Barrel length
- 450.9 mm17.75 insource
Published as 17.75 in; 1 in = 25.4 mm exactly.
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
- not recorded
Chamberings
- .30 Carbineprimary15 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.
- M1 carbine904.2 mm35.60 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. M1 carbine records no height, so its outline is drawn at the type's proportion — that height is part of the shape, not a measurement.
Detail
The most-produced American small arm of the Second World War, and the one that is hardest to argue about because people keep comparing it to the wrong thing. It was not meant to replace the M1 Garand. It was meant to replace the pistol carried by men whose hands were full of something else, and against a pistol it is an enormous improvement: three times the muzzle energy, four times the useful range, and a weight of 2.36 kg that a mortar crewman will actually keep with him.
Winchester’s short-stroke tappet gas system is the mechanically interesting part — a piston moves about 3 mm, strikes the operating slide and stops. David Williams patented it, and it turns up afterwards in the Ruger Mini-14, the SKS and a long line of others.
Its reputation for stopping nobody in Korea has two components that are usually conflated: the cartridge is genuinely modest, and the rifle’s early magazines and cold-weather lubricants were genuinely bad.
The article’s rate-of-fire figure belongs to the selective-fire M2 variant rather than to this rifle, so no cyclic rate is recorded here.
References
This entry's own bibliography. Every citation key on this page resolves into this list.
- M1 carbine · Wikipedia · 1370823947 · read 2026-08-31 · CC BY-SA 4.0
Last verified 2026-08-31 · review status: agent-populated