Are .308 Winchester and 7.62 × 51 mm NATO the same?
.308 Winchester is a civilian cartridge designation. 7.62 × 51 mm NATO identifies a military standard. Their names should not simply be swapped in technical information. Similar-looking cartridges are not automatically interchangeable.
.308 Winchester is a civilian cartridge designation. 7.62 × 51 mm NATO identifies a military standard. Their names should not simply be swapped in technical information. Similar-looking cartridges are not automatically interchangeable.
Assessment depends on cartridge and chamber dimensions and their permitted tolerances. Headspace also matters: it is a dimension defined by the design of the closed action. SAAMI notes that military-surplus firearms may allow greater values under their standard than the corresponding civilian standard. This is not a blanket statement about every modern firearm.
Pressure figures can likewise be compared only with their associated measurement methods. Two values from different tables may otherwise create a misleading impression. A single malfunction does not prove a universal cause such as a fundamentally different shoulder angle.
What counts is the marking and the firearm manufacturer’s explicit approval for the specific model. Unclear compatibility requires competent professional assessment. This explanation of terminology is not permission to interchange ammunition.
7,62 × 51 mm NATO — Dimensions, energy and range
- A · Overall cartridge length: 71.12 mm
- B · Case length: 51.18 mm
- C · Bullet diameter: 7.82 mm
Dimensions are taken from the table. Shape and proportions are simplified; the exposed bullet tip varies with the load. Not a scale standard or manufacturing drawing.
Drawing: Weitschuss
- Case length
- 51.18 mm
- Bullet diameter
- 7.82 mm
- Overall cartridge length
- 71.12 mm
- Muzzle energy E₀
- 3346 J (9.53 g · source example)
- Range context
- No sufficiently qualified range figure was taken from the reviewed sources.
Source dimensions in inches converted to millimetres and rounded.
What the dimensions mean
Case length measures the case without the bullet; overall length measures the complete cartridge. Bullet diameter is distinct from bore calibre. Sources may give nominal or maximum dimensions, so rounded figures can differ slightly. This overview is not a dimensioned standard drawing and does not establish interchangeability.
Understanding energy
E₀ is kinetic energy at the muzzle. It depends on bullet mass and velocity. These figures refer to selected examples from the sources, not every load of this calibre. Bullet design, barrel length and test conditions affect the result. A range of examples is neither a complete market comparison nor guaranteed minimum and maximum performance.
Understanding range
A sporting application distance describes a use case. Supersonic range is the distance over which a particular bullet remains faster than sound under specified conditions. Both differ from maximum flight distance. The cartridge name alone cannot provide a reliable range limit without load and condition details. These distances are neither hunting recommendations nor safety distances.
Data sources: Wikipedia · Source check 2026-10-04