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The Surprising Truth About 5.56 Ammo: Myths and Facts You Can't Ignore

The Surprising Truth About 5.56 Ammo: Myths and Facts You Can't Ignore

The Best 5.56 Ammo

FN Herstal created the 5.56 x 45mm NATO cartridge in the late 1970s, and it is a .22-caliber round intended for use in military rifles. The .223 Remington cartridge used in the M16 military rifle was based on the original ArmaLite-15 (AR-15) rifle's round, which was produced by Remington in 1957.

The top military officials were so dissatisfied with the .223 Remington's performance that they literally demanded a modification so that it could better penetrate armor and hard targets at long range. In October of 1980, the cartridge was modified to fire a 62-grain full metal jacket (FMJ) bullet that contains a 7-grain steel core penetrator in the M855 variant. This round is now known as 5.56 NATO.

5.56x45mm ammo is a type of rifle ammunition used in firearms chambered for the 5.56x45mm cartridge. It is typically used in assault rifles and other types of firearms that are designed to fire intermediate cartridges. The 5.56x45mm cartridge was originally developed by NATO in the late 1950s as a replacement for the 7.62x51mm cartridge, which was considered too powerful for use in lightweight assault rifles. The 5.56x45mm cartridge is characterized by its relatively small size, lightweight, and high velocity, which give it good accuracy and terminal performance at intermediate ranges. It is widely used by military forces and law enforcement agencies around the world.

Many individuals mistakenly believe that the .223 Remington and the 5.56x45mm NATO cartridges are identical, despite the fact that they are not. True, the two cartridges are remarkably identical to one another. The .223 and 5.56mm cartridges may sound similar at first glance, but there are significant differences between them that go beyond the designations. The current lineup of 5.56 NATO ammunition includes the M855/SS109, SS110, and SS111 rounds. 

Pronounced "five-five-six," the 5.56x45mm NATO round is the standard ammunition for weapons issued to NATO member states. In the Vietnam War, it replaced the .50 caliber .458 Winchester as the primary ammunition of the United States military. 
SAAMI regulations for the .223 Remington imply a maximum chamber pressure of 55,000 psi. Contrarily, the 5.56 casing can withstand pressures of up to 61 bar. Because the chamber of a rifle chambered in .223 Remington is not rated to take the pressure of a 5.56 round, you should never fire a 5.56 round from a firearm chambered in .223 Remington.

Fast adoption of the .223 occurred in both AR platform and bolt action rifles by all major manufacturers. It's great for target practice and varmint hunting thanks to its light recoil and flat trajectory. While 55, 62, and 69 grain .223 Remington bullets are the most often found bullet weights in most gun shops and sporting goods stores, there is a wide range of.223 Remington ammo is available to suit a wide range of needs.

The 5.56 If you're looking for an infantry fighting caliber, The 5.56 NATO is one of the greatest options. This common military cartridge has served its country well for decades. Even though it has flaws, the cartridge has proven to be an effective weapon in combat. Nevertheless, 5.56 ammo has a shorter length than many other popular calibers such as the 7.62 NATO round or .308 Winchester.  It is easier significantly easier to transport, because of its lighter weight which also enables a larger combat loadout. 

The military's requirement for a less recoiling battle rifle/carbine led to the development of the .223 and 5.56x45mm rounds, which is still a major success and only has rapidly grown in popularity. The .308 Winchester cartridge is an effective rifle round, although it has a somewhat larger case and can only handle heavier bullets. Because of all of these factors, firing a .308 produces significantly higher felt recoil. The 5.56x45mm has a lower felt recoil, allowing for faster follow-up shots and better accuracy when engaging targets in semi-automatic or fully automatic fire.

Shop at and find a wide selection of your favorite .223 & 5.56 NATO ammo now!
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