Sub-caliber training is used to save wear and expense when training with a larger gun by use of smaller weapons (sometimes, but not always, with very similar ballistic characteristics). The smaller weapons could be inserted into the larger weapon's barrel, externally attached to the barrel or mounted above the weapon.
Examples include
2.25-Inch Sub-Caliber Aircraft Rocket to train aircraft pilots to shoot aerial rockets that emerged during WWII, or the M303 Sub-Caliber insert for the
M120 mortar
The Soltam K6 is a 120 mm (4.75 inch) mortar that was developed by Soltam Systems of Israel. It is the long-range version of the Soltam K5 and has replaced older systems, such as the M30, in several armies including the United States Army. ...
that allows the mortar to use ammunition
MORTARS - DEPARTMENTS OF THE ARMY TECHNICAL ORDER 11W2-5-13-21
/ref> or the M49A1 sub-caliber device, which used 7.62×51mm NATO
The 7.62×51mm NATO (official NATO nomenclature 7.62 NATO) is a rimless, bottlenecked rifle cartridge. It is a standard for small arms among NATO countries.
First developed in the 1950s, the cartridge had first been introduced in U.S. service fo ...
rifle rounds in the M67 recoilless rifle
The M67 recoilless rifle is a 90 mm (3.55 inch) anti-tank recoilless rifle made in the United States and later in South Korea. It could also be employed in an anti-personnel role with the use of the M590 antipersonnel round. It was designed ...
. These devices/weapons have been used for guns as large as the main guns of battleship
A battleship is a large armored warship with a main battery consisting of large caliber guns. It dominated naval warfare in the late 19th and early 20th centuries.
The term ''battleship'' came into use in the late 1880s to describe a type of ...
s.
See also
* Caliber conversion sleeve
A caliber conversion sleeve or adapter sleeve is a device which can be used to non-permanently alter a firearm to allow it to fire a different cartridge than the one it was originally designed to fire. The different cartridge must be smaller in s ...
* Spotting rifle
A spotting rifle or ranging gun is a small-calibre rifle used as a sighting device for artillery. The ballistics of the spotting rifle are matched to those of the artillery piece, so that if a shot from the spotting rifle lands on the target, it m ...
References
Military education and training
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