Browning-Colt Mk12 Mod 3 (20 mm)

Description

The Colt-Browning Mk 12 Mod 3 is an advanced derivative of the 20 mm AN/M3 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 higher muzzle velocity, courtesy of the new electrically-primed cartridges designed specifically for the Mk 12. While these new cartridges, designated the Mk 100 series by the US Navy, had the same caliber and casing length as the 20x110 mm Hispano-Suiza rounds fired by the earlier AN/M3 cannon, the two types were in no way compatible, owing to the Mk 100 series having different casing dimensions.

The Mk 12 Mod 3 and its sibling, the Colt-Browning Mk 12 Mod 0, operate in the same manner - both are pneumatically-charged combination gas blowback weapons firing electrically-primed ammunition at a rate of 1000 rounds per minute - and only differ in a couple of areas, specifically relating to the recoil system and receiver body design. These differences stemmed from the different feeder systems used; the Mk 12 Mod 0 used a Mk 7 pneumatic feeder driven by a 3000 psi nitrogen bottle, while the Mk 12 Mod 3 used a simpler, albeit heavier, Mk 9 rotary recoil-operated feeder.

Vehicles equipped with this weapon

• F3H-2
• F8U-2
• F-8E
• ▄F-8E(FN)
• FJ-4B
• FJ-4B VMF-232

General info

Tactical and technical characteristics

• Rate of Fire: 996 rounds/min
• Individual Gun Burst Mass: 1.83 kg/sec
• Muzzle Velocity: 1,012 metres/sec
• Projectile Mass: 110 grams
• HE-I Filler Mass: 14 grams
• Tracer Colour: Red

Available ammunition

The Mk 12 cannon fires 20 x 110 mm USN ammunition, which was developed from the 20 x 110 mm Hispano-Suiza ammunition used by the AN/M2 and AN/M3 cannons.

The Mk 12 Mod 3 cannon can be equipped with the following belts:

• Default: AP-T · HEI · HEI

These are comprised of Mk 106 HEI and Mk 108 AP-T rounds and are the stock belts that come with the cannon.

• Universal: AP-T · HEI

These general-purpose belts are made up of the same HEI and AP-T rounds as the default belts.

• Ground targets: AP-T · AP-T · HEI · AP-I

Intended to be used against armoured ground targets, these boast a belt made up almost entirely of armour piercing ammunition. It features Mk 106 HEI, Mk 107 AP-I, and Mk 108 AP-T rounds.

• Air targets: AP-T · HEI · AP-I · HEI

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.

• Stealth: AP-I · HEI · HEI · HEI

These belts contain the most HEI rounds of any available for the Mk 12, with Mk 106 HEI and Mk 107 AP-I rounds.

Penetration statistics
Belt	Penetration @ 0° Angle of Attack (mm)
	10 m	100 m	500 m	1,000 m	1,500 m	2,000 m
Default	33	31	27	24	19	14
Universal	33	31	27	24	19	14
Ground targets	36	33	27	24	19	14
Air targets	36	33	27	24	19	14
Stealth	36	33	27	22	17	14

Comparison with analogues

Comparable ammunition

• 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 percussively primed cartridges on all other Hispano variants. Much like the AN/M3, it's 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 20 x 110 mm Hispano ammunition, which has a higher projectile mass than the 20 x 110 mm 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, a 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 a 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 20 mm cannons modification has been unlocked.

Pros and cons

Pros:

• Higher velocity ammunition means less lead is required against manoeuvring 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 its 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 the weapon in more detail than in the introduction. If the historical reference turns out to be too long, take it to a separate article, taking a link to the article about the weapon 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></ref>, as well as adding them at the end of the article with <references />.

Media

Excellent additions to the article would be video guides, screenshots from the game, and photos.

See also

• Browning-Colt Mk12 Mod 0 (20 mm)
• AN/M3 (20 mm)
• Hispano Mk.V (20 mm)
• M24A1 (20 mm)
• FMC T-160 (20 mm)
• M39A1 (20 mm)

External links

• [Wikipedia] Colt Mk 12 cannon
• NAVWEPS OP 1866 - 20-mm Aircraft Gun Mark 12 Mods 0, 2, and 3; Description, Operation and Maintenance (PDF - Download required for view!)
• 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)