Image credit
- Title
- File:Heckler & Koch MP5-1.jpg
- Author
- Heckler_&_Koch_MP5.jpg : Samuli Silvennoinen derivative work: Hic et nunc(attribution required)
- Licence
- CC BY-SA 3.0
- Source
- https://commons.wikimedia.org/wiki/File:Heckler_&_Koch_MP5-1.jpg
How Muzzle energy is calculated
E = ½ · m · v²
Inputs
- m7.452 g115.0 grverifiedsource115 gr as published, converted to grams.
- v359.7 m/s1,180 fpsverifiedMeasured with a 101.6 mm barrel, not this arm's 225 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 101.6 mm359.7 m/s1,180 fpsverifiedsource1180 fps as published.
Assumptions
- This figure belongs to a 101.6 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_firearm2.54 kg5.600 lbverifiedsourceThe MP5K is published at 2 kg.
- v_recoil1.055 m/s3.462 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
- capacity30verifiedsourceBox magazines of 15, 30, 40 and 50 rounds; 50- and 100-round drums exist.
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
- m7.452 g115.0 grverifiedsource115 gr as published, converted to grams.
- v359.7 m/s1,180 fpsverifiedMeasured with a 101.6 mm barrel, not this arm's 225 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
- mass7.452 g115.0 grverifiedsource115 gr as published, converted to grams.
- diameter9.03 mm0.3555 inverifiedsourceCartridge maximum, dimension G1.
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
- mass7.452 g115.0 grverifiedsource115 gr as published, converted to grams.
- velocity359.7 m/s1,180 fpsverifiedMeasured with a 101.6 mm barrel, not this arm's 225 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
- n30verifiedsourceBox magazines of 15, 30, 40 and 50 rounds; 50- and 100-round drums exist.
- rpm800 rpmverifiedsourceThe MP5K is published at 900 rounds/min and the suppressed MP5SD at 700.
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
- Submachine gun
- Action
- Self-loading
- Fire modes
- Semi-automatic
- Burst
- Fully automatic
- Operating system
- Blowback, roller-delayed
- Designed in
- Germany
- Introduced
- 1966
- Production
- 1966–present
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
- not recorded
Chamberings
- 9x19mm Parabellumprimary30 rounds
- .40 S&W30 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.
- Heckler & Koch MP5680 mm26.77 in
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.
Detail
Take the roller-delayed breech from the G3 battle rifle and build it at pistol scale. Two rollers in the bolt head are forced outwards into recesses in the barrel extension; opening the breech means camming them back in against an inclined locking piece, and the mechanical disadvantage of that geometry is what delays the bolt. There is no gas system and no locked breech in the usual sense.
What it buys is a submachine gun that fires from a closed bolt. Every open-bolt design — the Uzi, the MP 40, the MAC-10 — lurches forward as a heavy bolt runs home before the round fires, and the shot is gone before the weapon has settled. The MP5’s bolt is already home; only the hammer moves. That difference is the reason police and hostage-rescue units adopted it almost universally in the 1970s and 80s.
The price is a fluted chamber that scars the brass, a bolt that must be closed by slapping the cocking handle down, and a manufacturing cost that no stamped open-bolt weapon comes close to.
It has been made under licence in at least six countries, several of them without one.
References
This entry's own bibliography. Every citation key on this page resolves into this list.
- Heckler & Koch MP5 · Wikipedia · 1367066672 · read 2026-08-31 · CC BY-SA 4.0
Last verified 2026-08-31 · review status: agent-populated