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Military Cartridge Stock Section
5.56 x 45mm NATO (.223 Remington)
The 223 Remington was introduced in 1957 as an experimental cartridge for the AR-15 rifle, as the
United States forces were looking to replace the 7.62x51mm NATO (308 Winchester) with a lighter recoil
cartridge with less range for closer combat situations.
In 1964 it was adopted by the United Stated Army as the 5.6x45mm Ball cartridge: M193.
Shortly after the United States Army adopted the cartridge, Remington indroduced the 223 Remington
to the general public for the sporting and hunting industry.
In 1977 NATO countries signed an agreement to select the 5.56×45mm cartridge to replace the 7.62x51mm NATO cartridge; however, due to the
devastating wound damage of the 55 grain M193, it was decided to use the
Belgian 62 grain SS109 projectile, which was soon standardized as the official NATO cartridge.
The .223 Remington and 5.56x45mm NATO are not actually identical, although, the outside case dimensions are approximately the same, the 5.56
x45mm NATO has a thicker walled case and is usually loaded to higher pressures.
Because of the higher NATO pressures, it is best not to use the 5.56x45mm NATO cartridge in a rifle chambered
for the lower pressured .223 Remington. Can you ? Up to you, but it is like firing a high presure proof cartridge
in your .223 Remington rifle,  so in time the stress may take it's toll. Safety First!  Check with the rifle's maker....
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There are 1,000's of different cartridges available in these two calibers (.223 Remington & 5.56x45mm NATO)
from many different countries and manufacturers.
We are in the process of buying many different Head-Stamps, from different makers, as we are getting requests
for different cartridges in these calibers.
Below are just a few now available , but we hope to add many more as time allows.
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