Browning-Colt Mk12 Mod 3 (20 mm)

Description

The Colt-Browning Mk 12 Mod 3 is an advanced derivative of the AN/M3 (20 mm) cannon, and became the standard cannon found on US Navy aircraft from the mid 1950s. Compared to the AN/M3 it replaced, the Mk 12 boasted a faster rate of fire and a higher muzzle velocity, courtesy of the new, electrically-primed cartridges designed specifically for the Mk 12.

Vehicles equipped with this weapon

• FJ-4B
• FJ-4B VMF-232

General info

Rate of Fire: 1000 rounds/min

Individual Gun Burst Mass: 1.83 kg/sec

Muzzle Velocity: 1012 metres/sec

Projectile Mass: 110 grams

HE-I Filler Mass: 14 grams

Tracer Colour: Red

Available shells

The Mk 12 cannon fires 20x110mm USN ammunition, which was developed from the 20x110mm Hispano-Suiza ammunition used on the AN/M2 and AN/M3 cannons.

The following belts can be found on the Mk 12 Mod 3 cannon:

• Default belts - These are comprised of Mk 106 HE-I and Mk 108 AP-T rounds ordered HE-I/HE-I/AP-T, and are the stock belts that come with the cannon.
• Universal belts - These general-purpose belts are made up of the same HE-I and AP-T rounds as the default belts, only in a repeating HE-I/AP-T order.
• Ground Target belts - Intended to be used against armoured ground targets, these boast a belt made up almost entirely of armour piercing ammunition. It features Mk 106 HE-I, Mk 107 AP-I, and Mk 108 AP-T rounds arranged in AP-T/AP-T/HE-I/AP-I order.
• Air Target belts - These belts are arranged in much the same way as the Universal belts. However, every fourth round is now a Mk 107 AP-I round, leaving the belts ordered as HE-I/AP-T/HE-I/AP-I.
• Stealth belts - These belts contain the most HE-I rounds of any available for the Mk 12, with Mk 106 HE-I and Mk 107 AP-I rounds in HE-I/HE-I/HE-I/AP-I order.

Comparison with analogues

AN/M3 - The predecessor to the Mk 12, and inferior in almost every way. It has a lower rate of fire, lower burst mass, and lower muzzle velocity than the Mk 12 Mod 3.

M24A1 - Derived from the AN/M3, this cannon uses electrically primed cartridges instead of the percussivelly primed cartridges on all other Hispano variants. Much like the AN/M3, its inferior in every way to the Mk 12 Mod 3.

Hispano Mk.V - The forerunner to the AN/M3, and by extension the Mk 12. As with the two above, it has a lower muzzle velocity, lower rate of fire, and lower burst mass than the Mk 12.

All three of the above weapons fire 20x110mm Hispano ammunition, which has a higher projectile mass than the 20x110mm USN used by the Mk 12, so each individual shell impact will do more damage.

M39A1 & FMC T-160 - These are the US Air Force equivalent to the Mk 12. They have a higher muzzle velocity, much higher rate of fire, and a higher burst mass. However, they have an individual projectile mass nearly 10% lower than that of the Mk 12, and rely more on the sheer number of rounds hitting the target than the size of the shell itself.

Usage in battles

The Mk 12 is an excellent general-purpose cannon - the high quantity of AP rounds in the Ground Targets belts are ideally suited to taking out lightly armoured vehicles, and the large amount of HE-I rounds in most other belts are easily capable of destroying any opponent. However, the higher rate-of-fire and higher muzzle velocity than the AN/M3 cannons found on the aircraft before it will require some getting used to, particularly when using these cannons against moving targets. Additionally, short bursts are required with a stock cannon, but are not a requirement once the New 20mm Cannons modification has been unlocked.

Pros and cons

Summarize and briefly evaluate the weaponry in terms of its characteristics and combat effectiveness. Mark pros and cons as a list.

Pros:

• Higher velocity ammunition means less lead is required against manoeuvering targets
• High rate-of-fire
• Can fire nearly 400 rounds before jamming when upgraded

Cons:

• As with other high rate-of-fire cannons, it will quickly deplete it's ammunition stores.
• Limited to fairly short bursts while stock to prevent jamming
• Inaccurate while stock

History

Examine the history of the creation and combat usage of this weapon. If the historical reference turns out to be too big, take it to a separate article, taking a link to an article about the vehicle and adding a block "/ History" (example: https://wiki.warthunder.com/(weapon-name)/History) and add a link to it here using the main template. Be sure to reference text and sources by using <ref>, as well as adding them at the end of the article.

Media

An excellent addition to the article would be a video guide, as well as screenshots from the game and photos.

See also

AN/M3 (20 mm)

Hispano Mk.V (20 mm)

M24A1 (20 mm)

FMC T-160 (20 mm)

M39A1 (20 mm)

External links

Colt Mk 12 cannon (Wikipedia)

NAVWEPS OP 1866 - 20-mm Aircraft Gun Mark 12 Mods 0, 2, and 3; Description, Operation and Maintenance (PDF)

The following documents also contain information about the Mk 12 cannon, as well as other types -

MIL-STD-637A - Machine and Automatic Guns and Machinegun Trainers Through 30-mm (PDF)

NAVORD OP 2215 - Navy Gun Type Ammunition (PDF)

Small-Caliber Ammunition Identification Guide, Volume 2 - 20-mm to 40-mm Cartridges (PDF)