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Weapons

The M27 Infantry Automatic Rifle: The Beginner’s Guide

November 18, 2022 by SOFREP 1 Comment

The M27 Automatic Rifle is the standard squad automatic weapon for all US Marines.

The M27 Infantry Automatic Rifle (IAR) is a select-fire weapon that chambers the NATO-standard 5.56x45mm cartridge. It is derived from the Heckler & Koch HK416 and is currently in service with the United States Marine Corps.

The M27 is often mistaken as just an upgraded version of the FN Minimi or even its modified version, but that isn’t exactly correct. The M27 is built explicitly for and issued to infantry soldiers (hence “Infantry” in its official designation) within an Infantry Battalion Task Force. With that being said, let’s take a look at everything you need to know about the M27 Infantry Automatic Rifle.

Introduction to the M27 Infantry Automatic Rifle

The M27 Infantry Automatic Rifle (IAR) is the standard squad automatic weapon for all United States Marine Corps. It is the supposed successor to the M249 Squad Automatic Weapon, providing soldiers with a more compact, lighter, and improved version of the standard general-purpose machine gun that can be useful in a wider variety of scenarios.

The IAR is also issued to infantry soldiers within an Infantry Battalion Task Force.

History of the M27 Infantry Automatic Rifle

The M249 Squad Automatic Weapon has been in US Army and Marine Corps since the early 1990s. It was developed to replace the M60 machine gun, which had been in service since the 1950s. The M249 entered service as the M249 SAW (Squad Automatic Weapon) but has since been replaced by the M27 Infantry Automatic Rifle (IAR). The M249 had a few problems when issued to troops, which were corrected in the M27.

The main problem with the M249 was that it was heavy. It was developed for use in the Humvee, but troops often had to carry it on foot. This was problematic because it was so heavy that infantrymen couldn’t use it effectively on the move. The M249 was also very difficult to change barrels on, which made it challenging to maintain in the field.

Design and Features of the M27 IAR

The M27 IAR was developed to give infantry squads a higher volume of fire than what could be provided by the standard issue M4 carbine, without the weight or recoil penalties of a belt-fed light machine gun. It is intended to supplement or replace the M249 Squad Automatic Weapon in certain roles.

The M27 IAR is gas operated with a rotating bolt and uses a short-stroke piston system. This system reduces fouling, increases reliability, and allows the use of suppressors with a slight decrease in performance. The barrel is free-floating and made of cold hammer-forged chrome-lined steel. It has a 1:7-inch twist rate and is fluted to reduce weight and increase cooling capacity. The handguard is made of aluminum and has Picatinny rails at the 3, 6, and 9 o’clock positions for mounting sights, lights, or other accessories.

The M27 IAR uses STANAG (NATO Standardization Agreement) magazines, also used in the M16 rifle and M4 carbine. It can also use 100-round Beta C-Mag magazines and PMAGs (Polymer Magazines) in 25-, 30-, and 40-round capacities. The stock is adjustable for the length of the pull and folds to the right side of the weapon for compactness.

The M27 IAR is a 5.56mm light machine gun. It can be fired either as a fully automatic or as a semi-automatic rifle. It is belt-fed, and the ammunition is stored in a 100-round plastic box attached to the side of the weapon. The M27 IAR is designed to be fired from the right shoulder and can be fired from the left shoulder, but this is not recommended.

The M27 IAR has a quick-change barrel, which can be changed in less than 10 seconds. It also has an adjustable telescopic stock, and it can be fired when the store is fully extended. In addition, the M27 IAR can be fired from the prone, crouching, standing, or standing offset positions.

How is the M27 Different from the M249 SAW?

The M27 IAR is significantly lighter than the M249 SAW. It has a weight of fewer than 9 lbs when fully loaded, and it has an overall length of 29″. The M249 SAW, on the other hand, had an overall length of 48″.

The M27 has a cyclic firing rate of 600 rounds per minute, compared to 900 rounds per minute for the M249. The M249 can also be fed from either a 100-round box or a 200-round belt, whereas the M27 can only use the 100-round belt. The M249 SAW also has an adjustable telescopic stock, but it can only be fired when the stock is fully extended, whereas the M27 can be fired with the stock in any position. Both weapons weigh 9 lbs when fully loaded.

How Much Does an M27 IAR Cost?

The M27 Infantry Automatic Rifle (IAR) costs $3,000 each. A new M27 IAR is expected to last for 40,000 rounds before needing to be replaced, and a mid-life rebuild is expected to occur after 25,000 rounds are fired.

Summary:

•The M27 Infantry Automatic Rifle (IAR) is a select-fire weapon that chambers the NATO-standard 5.56x45mm cartridge and is derived from the Heckler & Koch HK416.
• The M27 IAR is gas operated with a rotating bolt and uses a short-stroke piston system. This system reduces fouling, increases reliability, and allows the use of suppressors with a slight decrease in performance.
• The M27 IAR has many features that distinguish it from other rifles, including its quick-change barrel, adjustable telescopic stock, and ability to be fired from the prone position.


Have you used both rifles before? Which one do you prefer?

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