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5.56 Nato

5.56 NATO is a rimless bottlenecked intermediate cartridge developed in the late 1970s in Belgium by FN Herstal. It was standardized as the second standard service rifle cartridge for NATO forces as well as many non-NATO countries.

Is 5.56 NATO more powerful than 223? The 5.56 NATO has a higher pressure than the 223 round and is one of the two major differences. The 5.56 NATO pressure is about 58,000 psi and the 223 round is approximately 55,000 psi.

Why does the military use 556 and not 223? Differences between the two are small but can have a large impact on performance, safety and weapon function. The first difference is the higher pressure level of the 5.56 NATO cartridge which runs at approximately 58,000 psi. A 223 Remington is loaded to approximately 55,000 psi.

Our 5.56 NATO uppers all come with a 100% satisfaction guarantee. Check them out here and if you have any questions, please reach out to our customer service team at 239-848-6757.

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    MCS Shorty 5" AR15 Complete Build Kit MCS Shorty 5" AR15 Complete Build Kit

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    Build the ultimate AR with the new MCS shorty 5" pistol build kit. This kit features all USA made parts as well as the 3.5 short buffer system.  Includes:  USA Made 3.5 Short Buffer System USA Made Lower Parts Kit USA Made 5.56 NATO AR-15...

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    MCS 7.5" 5.56 NATO PISTOL BARREL USA MADE

    7.5" 5.56 NATO PISTOL BARREL USA MADE

    Features: 7.5” barrel chambered for .223/5.56 NATO Pistol length gas system SOCOM profile with .750” gas block shelf 4150 Chrome Moly Vanadium Steel with Nitride finish 1:7 button rifling with .0001” tolerances 1/2x28 threads Dimpled...

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    7.5" Skeletonized Pistol Complete Upper Build Kit Features: Skeletonized pistol brace BCA 4150 7.5″5.56 M4 BarrelBird cage MuzzleCarbine Length Gas TubeLow Profile .750 Gas Block7'' M-LOK Free Float Handguard Mil Spec Dust...

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    16" Skeleton Complete Upper Build Kit Minus Lower Features: BCA 16'' M4 Contour 1:7 Twist Barrel Bird cage MuzzleCarbine Length Gas TubeLow Profile .750 Gas Block15'' M-LOK Free Float Handguard Mil Spec Dust CoverForward Assist Mil-spec...

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    16" Omega Complete Upper Build Kit Minus Lower Features: BCA 16'' M4 Contour 1:7 Twist Barrel Bird cage MuzzleCarbine Length Gas TubeLow Profile .750 Gas Block15'' M-LOK Free Float Handguard Mil Spec Dust CoverForward Assist Mil-spec lower...

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  • MCS Alpha 16" AR15 Complete Build Kit MCS Alpha 16" AR15 Complete Build Kit

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    16" Alpha Complete Upper Build Kit Minus Lower Features: BCA 16'' M4 Contour 1:7 Twist Barrel Bird cage MuzzleCarbine Length Gas TubeLow Profile .750 Gas Block15'' M-LOK Free Float Handguard Mil Spec Dust CoverForward Assist Mil-spec lower...

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  • MCS Cobra 16" AR15 Complete Build Kit MCS Cobra 16" AR15 Complete Build Kit

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    16" Cobra Complete Upper Build Kit Minus Lower Features: BCA 16'' M4 Contour 1:7 Twist Barrel Bird cage MuzzleCarbine Length Gas TubeLow Profile .750 Gas Block15'' M-LOK Free Float Handguard Mil Spec Dust CoverForward Assist Mil-spec lower...

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