12 gauge
SAAMI standard
Also known as 12/70, 12 bore — the same cartridge under different names, all of which find this page.
Dimensions and pressure
Generated from the schema, like every specification table on this site, so a figure recorded on this entry cannot be missing from the table.
Identity
- Designed by
- not recorded
- Introduced
- not recorded
- Production
- not recorded
- Standards body
- SAAMI
- Case type
- Shotshell
- Case shape
- not recorded
Dimensions
- Bullet diameter
- not recorded
- Bore diameter
- 18.42 mm0.7252 insource
Bore diameter of the SAAMI 12-gauge standard smoothbore test barrel, 0.725 in.
- Case length
- 69.8 mm2.748 insource
Cartridge maximum for the 12/70 shell, dimension l. This is the fired length of the unfolded case, which the chamber must accept.
- Overall length
- 63.9 mm2.516 insource
Length of the loaded M19 buckshot cartridge, 2.515 in. A crimped shotshell is shorter than the shell length it is named for.
- Rim diameter
- 22.45 mm0.8839 insource
Cartridge maximum, dimension g.
- Neck diameter
- not recorded
- Base diameter
- 20.6 mm0.8110 insource
Cartridge maximum, dimension d.
Pressure
- Maximum pressure
- 74 MPa10,733 psisource
Pmax for the 12/70 shell, 740 bar.
- Pressure standard
- C.I.P.
SAAMI and C.I.P. measure pressure differently and their figures are not interchangeable, which is why the body is always named beside the figure.
Loads
Velocity is recorded per barrel length as published. A gun page interpolates between these points and never projects beyond them.
Power-Shok 1 oz rifled slug
Federal
- Bullet mass
- 28.38 g438.0 grsource
438 gr as published, converted to grams. One ounce.
- Cartridge mass
- not recorded
- Bullet type
- Rifled slug
- G1 BC
- not recorded
- G7 BC
- not recorded
| Barrel | Velocity |
|---|---|
| 762 mm30.00 in | 490.7 m/s1,610 fps |
Chambered in
Computed from every entry that lists this cartridge. Nothing here is hand-maintained.
- Beretta 682
Fabbrica d'Armi Pietro Beretta
- Browning Auto-5
FN Herstal
- Remington Model 870
Remington Arms
Gallery
Image credit
- Title
- Shotshell 001
- Author
- Rookie_Rover
- Licence
- Public domain
- Source
- https://commons.wikimedia.org/wiki/File:Shotshell_001.jpg
Detail
A gauge is not a calibre. The number counts how many spherical lead balls of bore diameter make up one pound, so a larger number means a smaller bore, and twelve of them weigh sixteen ounces. That is why this entry records a bore diameter and no bullet diameter: what leaves the muzzle may be nine hardened pellets, a single slug or a sabot, and choosing one of those to call the projectile would be inventing a fact about a cartridge that does not have one.
Shell length is the other trap. A shell described as 2-3/4 inch measures about 64 mm loaded and crimped and opens to about 70 mm when fired, and it is the fired length the chamber has to accommodate. The two numbers below are both recorded for that reason.
This entry has one load. The United States Army’s M19 buckshot cartridge is fully documented in a public-domain manual which gives its weight, its length, its pressure and its velocity, and does not give the weight of the shot charge, so there is no honest way to enter it as a load here.
References
- C.I.P. TDCC datasheet, Cal. 12 · Tab. VII, dated 1984-06-14, revision 2018-10-17 · read 2026-08-27
- ANSI/SAAMI Z299.2, Shotshell Ammunition · Z299.2-2019, approved 2025-09-23 · read 2026-08-27
- TM 43-0001-27, Army Ammunition Data Sheets: Small Caliber Ammunition · TM 43-0001-27, 29 April 1994 · read 2026-08-27
- Power-Shok Rifled Slug, 12 Gauge, 438 grain, 2-3/4 in (F127 RS) · read 2026-08-27
Last verified 2026-08-27 · review status: spot-checked