5.56x45 Ammo For Sale

Used in the M4 series and other military-style rifles, the 5.56x45 is a hugely popular cartridge. Besides military uses, 5.56 ammo is commonly used in competition firearms, home defense applications, and is replacing shotguns in many police cruisers. Learn More

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  1. Lake City 5.56x45 Ammo - 1000 Rounds of 62 Grain FMJ Ammunition

    18 In stock now
    Image For 1000 Rounds Of 62 Grain FMJ-BT Boxer Brass 5.56x45 Federal Ammunition
    $320.00 Price

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    • 1000 Rounds
    • Made by Federal

    • New Condition
    • 1000 Rounds
    • Made by Federal
    • American-made Range
    • 32¢ Cost Per Round
    • 3020 FPS Muzzle Velocity
    • 1255 ft lbs Muzzle Energy
    • Federal SKU XM855CS
    • UPC 604544642827
  2. Federal 5.56x45 Ammo - 1000 Rounds of 55 Grain FMJ-BT Ammunition

    12 In stock now
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    $320.00 Price

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    • 1000 Rounds
    • Made by Federal

    • New Condition
    • 1000 Rounds
    • Made by Federal
    • American-made Discount Range
    • 32¢ Cost Per Round
    • 3165 FPS Muzzle Velocity
    • 1282 ft lbs Muzzle Energy
    • Federal SKU XM193BK
    • UPC 029465560713
  3. Fiocchi 5.56x45 Ammo - 1000 Rounds of 55 Grain FMJBT M193 Ammunition

    3 In stock now

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    Image For 1000 Rounds Of 55 Grain FMJ-BT Boxer Brass 5.56x45 Fiocchi Ammunition
    $324.99 Price

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    • 1000 Rounds
    • Made by Fiocchi

    • New Condition
    • 1000 Rounds
    • Made by Fiocchi
    • Foreign Discount Range
    • 32.5¢ Cost Per Round
    • 3240 FPS Muzzle Velocity
    • 1280 ft lbs Muzzle Energy
    • Fiocchi SKU 556M193L
    • UPC 762344864259
  4. PMC 5.56x45 Ammo - 1000 Rounds of 55 Grain FMJ Ammunition

    13 In stock now
    Image For 1000 Rounds Of 55 Grain FMJ-BT Boxer Brass 5.56x45 PMC Ammunition
    $330.00 Price

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    • 1000 Rounds
    • Made by PMC

    • New Condition
    • 1000 Rounds
    • Made by PMC
    • Foreign Discount Range
    • 33¢ Cost Per Round
    • 3270 FPS Muzzle Velocity
    • 1306 ft lbs Muzzle Energy
    • PMC SKU 5.56X
    • UPC 20741569010119
  5. Hornady Frontier 5.56x45 Ammo - 1000 Rounds of 55 Grain FMJ M193 Ammunition

    17 In stock now

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    Image For 1000 Rounds Of 55 Grain FMJ Boxer Brass 5.56x45 Hornady Ammunition
    $330.00 Price

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    • 1000 Rounds
    • Made by Hornady

    • New Condition
    • 1000 Rounds
    • Made by Hornady
    • American-made Discount Range
    • 33¢ Cost Per Round
    • 3240 FPS Muzzle Velocity
    • 1282 ft lbs Muzzle Energy
    • Hornady SKU FR206
    • UPC 090255711424
  6. PMC 5.56x45 Ammo - 1000 Rounds of 62 Grain FMJ Ammunition

    16 In stock now
    Image For 1000 Rounds Of 62 Grain FMJ Boxer Brass 5.56x45 PMC Ammunition
    $334.99 Price

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    • 1000 Rounds
    • Made by PMC

    • New Condition
    • 1000 Rounds
    • Made by PMC
    • Foreign Discount Range
    • 33.5¢ Cost Per Round
    • 3100 FPS Muzzle Velocity
    • 1323 ft lbs Muzzle Energy
    • PMC SKU 5.56K
    • UPC 20741569010126
  7. Prvi Partizan 5.56x45 Ammo - 1000 Rounds of 55 Grain FMJBT M193 Ammunition in Ammo Can

    12 In stock now

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    Image For 1000 Rounds Of 55 Grain FMJ-BT Boxer Brass 5.56x45 Prvi Partizan Ammunition
    $344.99 Price

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    • 1000 Rounds
    • Made by Prvi Partizan

    • New Condition
    • 1000 Rounds
    • Made by Prvi Partizan
    • Foreign Discount Range
    • 34.5¢ Cost Per Round
    • 3240 FPS Muzzle Velocity
    • 1282 ft lbs Muzzle Energy
    • Prvi Partizan SKU PPN5561MC
    • UPC 8605003810117
  8. Winchester 5.56x45 Ammo - 1000 Rounds of 62 Grain FMJ Ammunition

    9 In stock now

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    Image For 1000 Rounds Of 62 Grain FMJ Boxer Brass 5.56x45 Winchester Ammunition
    $405.00 Price

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    • 1000 Rounds
    • Made by Winchester

    • New Condition
    • 1000 Rounds
    • Made by Winchester
    • American-made Range
    • 40.5¢ Cost Per Round
    • 3000 FPS Muzzle Velocity
    • Winchester SKU Q3269
    • UPC 020892213371C
  9. Winchester 5.56x45 Ammo - 1000 Rounds of 50 Grain Frang. Ammunition

    6 In stock now

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    Image For 1000 Rounds Of 50 Grain Frang. Boxer Brass 5.56x45 Winchester Ammunition
    $440.00 Price

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    • 1000 Rounds
    • Made by Winchester

    • New Condition
    • 1000 Rounds
    • Made by Winchester
    • American-made Discount Range
    • 44¢ Cost Per Round
    • 3000 FPS Muzzle Velocity
    • 899 ft lbs Muzzle Energy
    • Winchester SKU USA556JF
    • UPC 50020892219828
  10. Black Hills Ammunition 5.56x45 Ammo - 500 Rounds of 77 Grain MatchKing OTM Ammunition

    13 In stock now

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    Image For 500 Rounds Of 77 Grain OTM Boxer Brass 5.56x45 Black Hills Ammunition Ammunition
    $549.99 Price

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    • 500 Rounds
    • Made by Black Hills Ammunition

    • New Condition
    • 500 Rounds
    • Made by Black Hills Ammunition
    • American-made Range
    • $1.10 Cost Per Round
    • 2750 FPS Muzzle Velocity
    • 1293 ft lbs Muzzle Energy
    • Black Hills Ammunition SKU D556N9
    • UPC 612710126385
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Perhaps one of the most iconic military cartridges, the 5.56x45mm NATO ammunition, commonly referred to as the 5.56 NATO, has been in active use in the United States Armed Forces since 1964.

5.56x45 NATO ammo features a rimless and tapered bottleneck case that measures 44.70mm (1.76 inches) in length and ranges from a 6.43mm diameter at its neck to a 9.58mm diameter at its base. This casing houses a boat-tailed bullet with a diameter of 5.70mm, or .224 inch. With both bullet and shell, the 5.56 cartridge reaches 57.40mm (2.26 inch) in length.

While the original 5.56x45mm bullet was 55 grain (gr) of lead, the standard bullet now weighs 62 gr and consists of a lead base topped with a steel penetrator. The added weight increases the ammunition’s penetration and velocity, improving its performance.

The ammunition uses a small rifle primer and the Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI) sets the maximum pressure for the round between 55,000 and 58,000 pounds per square inch (psi), but variations are available with  maximum pressures as high as 62,000 psi.

Although the round was originally designed as a military cartridge, the 5.56x45mm NATO has found a home among American civilian shooters. It’s especially popular in military-style semi-automatic carbines.

The Development of 5.56x45mm Ammunition

The 5.56x45 cartridge developed from a need for a faster firing automatic weapon and ammunition. After extensive research, the military determined it needed something that could fire small caliber, high velocity (SCHV) projectiles and do so quickly.

In 1957, the U.S. Continental Army Command (CONARC) requested Eugene Stoner, a lead engineer and designer at Armalite, for a scaled down version of his AR-10, where the “AR” stands for Armalite Rifle, not assault rifle. The AR-10, while effective, fired the first, and at the time only, NATO cartridge – the 7.62x51mm NATO, which is similar in size to the .308 Winchester.

With the request for the new firearm, CONARC also released a call for an ammunition that could go with it. The military knew what they wanted for the new ammunition, primarily a .22-caliber bullet with the following requirements:

  • Maintained supersonic speeds, above 1,080 feet per second (fps) at 500 yards
  • Penetrated an Army-issued steel helmet at 500 yards
  • Penetrated a .135-inch steel plate at 500 yards
  • Reached the ballistic performance and accuracy of M2 ball ammunition, the military version of the .30-06 Springfield
  • Wounded as efficiently as the M1 Carbine, which fired .30 Carbine cartridges

The CONARC required the firearm have both automatic and semi-automatic firing and weight six pounds or less. The firearm needed a magazine that could hold at least 20 rounds.

The ammunition’s development began under Springfield Armory’s Earle Harvey. Starting with a .222 Remington, Harvey lengthened the case to allow for more powder and called it the .224 Springfield. Before he could continue his work on the new military round, Springfield Armory ordered he cease, as they were working on a new rifle chambered in 7.62mm and didn’t want to have a competing round.

Stoner then turned to Frank Snow of Sierra Bullet and Robert Hutton, who worked as the technical editor of Guns & Ammo magazine, and together they collaborated on a 55 gr bullet with a muzzle velocity of 3,300 fps, which could meet the demands of CONARC’s requirements.

By 1959, the AR-15 and the 5.56x45mm cartridge were ready for their first round of testing. By 1961, marksmanship testing had 45 percent of shooters reaching expert certification, while only 22 percent could reach the same level of certification with the M14, leading to the first major order – 80,000 AR-15 rifles for the Air Force.

In 1962, Remington submitted the ammunition’s specifications to SAAMI as the civilian version of the 5.56x45mm, the .223 Remington, which it accepted. By 1964, the U.S. Army officially adopted the 5.56mm Ball Cartridge, M193, or what is commonly referred to as the 5.56 NATO, to be used with its newest firearm, the M16 (or, in civilian terms, the AR-15).

After combat testing during the Vietnam War, the 5.56 NATO and the .223 soon became one of the most popular centerfire cartridges not only in America, but internationally.

Its popularity has been reinforced with the ammunition’s light weight, as well as the light weight of the firearms chambered for it. With the 5.56 NATO, significantly more rounds could be carried both in the weapon and on the person during combat, with no more additional weight.

What’s more, the ease of use, including low bolt thrust and almost non-existent perceived recoil, made the firearm easy to shoot and more shooters were able to become proficient with the firearm and excel with it.

As time progressed, law enforcement agencies and militaries throughout the world, including many non-NATO countries, have opted for the cartridge and it’s become a favorite to an increasing number of U.S. civilians.

The Types of 5.56 NATO Ammo

The original 5.56 NATO was first loaded with a full metal jacket (FMJ) bullet weighing 55 gr that exited the barrel of the new AR-15 rifle at more than 3,200 fps. In 1984, ammunition was adopted by the nations of the North Atlantic Treaty Organization, or NATO, which is an intergovernmental military alliance between countries in North America and Europe.

With this NATO adoption came a few changes, most notably the addition of a steel penetrator tip in the bullet. Now called the M855, this bullet weighed a slightly heavier 62 gr and had a slightly lower velocity of around 3,100 fps. Although it doesn’t leave the muzzle as fast as the original 55 gr bullet, this heavier projectile has a stronger sustained velocity.

Because of these changes to the ammunition, the firearms needed slight altercation as well. With a heavier bullet (an increase of seven gr from the M193 to the M855), the firearm barrel needed a tighter rifling twist, at a ratio of 1:7, to help stabilize the bullet’s weight gain. This change in rifling led to improved penetration and greater accuracy than the original round.

Beyond the M855, other military variations arose, including the Mk318, a 62 gr barrier-blind round, and for precision marksmanship, the Mk262 Open Tip Match bullet.

For civilian shooters, 5.56 NATO cartridges can be found in a variety of configurations, including:

  • Full metal jacket (FMJ): FMJ rounds feature lead bullets encased, or jacketed, in copper or another hard metal; this metal jacket allows the projectile to keep its shape until impact and leads to greater penetration
  • Full metal jacket-boat tail (FMJ-BT): With FMJ-BT ammo, shooters get a bullet that’s both jacketed and tapered at the rear, resembling the shape of a boat; this shape allows for better accuracy and a more stable flight than other ammunitions
  • Hollow point boat tailed (HPBT): HPBT rounds feature a projectile that has a hollow point into the center of the bullet, as well as a boat-like shape to the back of the bullet; these cartridges are often seen in long-range hunting for big game animals and are known for their rapid expansion
  • Frangible: Frangible bullets don’t expand like traditional FMJ or jacketed hollow point bullets, but instead fragment into many smaller pieces; this fragmentation eliminates the risk of over penetration and can increase the size and internal damage of a wound
  • Open tip match (OTM): Perhaps one of the most controversial types of ammo, OTM rounds feature a jacketed lead bullet; like a hollow point, the projectile has an open tip, but unlike hollow points, it’s not designed to expand; instead the bullet has a poured core, which makes it extremely accurate and a favorite amongst competition target shooters

There are also speciality 5.56 NATO variations, including rounds like GMX by Hornady, which features a monolithic construction that’s tougher than cooper, and the Triple Shock X (TSX) by Barnes Bullets. TSX bullets are solid copper and designed for hunting, with their consistent and uniform expansion.

The 5.56 NATO Performance

When it comes to performance, the standard 5.56 NATO proves its worth. The cartridge penetrates to a depth of 38-51 cm (15 to 20 inches) in soft tissue and, when the impact occurs at a velocity higher than 2,500 fps, the projectile is likely to fragment into multiple pieces, causing significant wound damage.

Some believe the 5.56 NATO is even strong enough to cause hydrostatic shock damage, where the soundwaves from the projectiles’ impact create tissue damage.

Even without hydrostatic shock, which is a theory and not accepted among all gun and ammunition experts, the 5.56 NATO projectile is designed to yaw after impact. When a bullet “yaws,” it moves side to side, creating a bigger wound cavity and more extensive damage than a bullet that travels a straight path.

Yet when this round is shot out of a short-barrelled carbine, it can sometimes fail to yaw and result in over-penetration and limited expansion.

The AR-15 and Bulk 5.56 Ammo

Popular worldwide, many firearm manufacturers have produced weapons chambered for the 5.56x45 cartridge – including Armalite, Bushmaster, and Colt, among others. But the most popular, by far, is Armalite’s AR-15 and the plethora of firearms that have been built in the semi-automatic AR-15 style.

Because these firearms are so prevalent, it’s become easy to find cheap 5.56 NATO ammo and 5.56x45mm bulk ammunition. Surplus 5.56 ammo can be found both in brick and mortar gun stores from coast to coast, and most major online ammunition stores.

Although most 5.56 NATO chambered firearms are semi-automatic, shooters can find pump-action rifles in the military round.

The 5.56x45 vs .223 Remington

Externally, there are no differences between the 5.56x45mm NATO and the .223 Remington. They have the same casing. Their projectiles are the same diameter. Side-by-side, there are no visible differences between the two, other than the headstamp. But inside, there are major differences, ones that can become extremely dangerous if ignored.

When discussing these two cartridges, it’s important to remember that the 5.56 NATO was designed as a military cartridge, while the .223 Remington has been designated for civilians since its onset. One was made for war, one to shoot varmint in the backyard.

It makes sense, then, that the 5.56 NATO has a different powder load, leading to a higher pressure. The military round averages a maximum pressure about 5,000 psi higher than the .223 Remington.

This pressure difference isn’t just because of powder difference (although that’s part of it), it also has to do with the difference in chamber leade. Chamber leade refers to the space between where a bullet sits at rest to where it engages in the rifling twist. The shorter the leade, the quicker the bullet engages, and the more pressure that’s created in the barrel.

Firearms chambered for the .223 have a shorter leade than those manufactured for the 5.56 NATO. Firearms manufactured for the military round have a chamber that’s actually slightly larger than those chambered for the .223 to reduce malfunctions and misfires from dirty guns, like those often seen in battlegrounds. These larger chambers have a longer leade and the 5.56 NATO is made accordingly.

So when a shooter takes the 5.56 NATO, which was designed to be fired from a rifle with a long leade, and puts it in a firearm chambered for the .223 Remington, it engages in the rifling quicker than it should and can drastically increase the pressure in the barrel, endangering not only the firearm, but the shooter as well.

Because .223 ammo is under a lower pressure than 5.56x45mm rounds, and has a shorter leade, the civilian ammunition can be fired without issue from the 5.56 NATO weapons.

To recap, it is NOT safe to fire 5.56 NATO ammunition from a firearm chambered to .223 Remington. But it IS safe to fire .223 Remington ammo from firearms chambered to the 5.56 NATO.

In many modern military-style firearms, the barrel is labeled with both chamberings, such as 5.56 NATO/.223 Rem.

As easy way to think about it is this: Consider the 5.56 NATO as a .223 +P. And like other +P ammunitions, a shooter shoulder never shoot the higher pressure ammo out of a barrel that’s not indicated for its pressure.

5.56x45mm Ballistics: Chart of Average 5.56x45mm Ballistics

Note: This information comes from the manufacturer and is for informational purposes only. The actual ballistics obtained with your firearm can vary considerably from the advertised ballistics. Also, ballistics can vary from lot to lot with the same brand and type load.

5.56x45mm Bullet WEIGHT Muzzle VELOCITY (fps) Muzzle ENERGY (ft. lbs.) TRAJECTORY (in.)
  Muzzle 100 yds. 200 yds. 300 yds. 400 yds. Muzzle 100 yds. 200 yds. 300 yds. 400 yds. 100 yds. 200 yds. 300 yds. 400 yds.
55 Grain NATO 3130 2740 2382 2051 1750 1196 917 693 514 372 1.1 0 -7.3 -23
75 Grain NATO 2910 2676 2543 2242 2041 1410 1192 1002 837 693 1.2 0 -7 -21
  • Click To Purchase This 5.56x45 Lake City Ammunition
    based on the 2 reviews below
  • Bill said:

    "I have tried different ammo with Sig 556. Its eats everything but I find Lake City 5.56 62gr --- No failures, Accurate @ 100 to 300 yards ( my club limits ) I have the feeling of complete depenability."

  • Russ said:

    "This is great ammo for the hybrid AR's.The brass is good for reloading and the 62 grain bullets stabilize well. Russ"

  • Click To Purchase This 5.56x45 Winchester Ammunition
    based on the 1 review below
  • Fiftysum said:

    "I just bought a Colt LE6920 5.65 caliber. The closest thing I ever shot was my M16 when I was in the Army during the Vietnam era -- a long time ago. So my review is not based on a comparison with any other ammo brand in this caliber. I bought Winchester because it is a known brand, is labeled for target use, and I feel it was available for a good price here on Ammo.com. I know there are some premium brands, which I will try eventually, and there are lots of brands I never heard of. Some of them may be good, I just don't know anything about them yet. I'm giving the Winchester 5.56 target ammo five stars in each category because my shots were consistently within one inch of the bullseye at 25 and 50 yards. That I hit the target at all at 100 yards I will count as okay because I didn't have a scope and I could just barely make out the 100-yard target with my not-so-good-as-when-I-was-20 eyesight. I qualified "sharpshooter" when I was in the Army, having missed "expert" by one shot. It makes me happy that this Colt M4 is as accurate, if not more so, than my Army M-16. Good ammo should give consistent results. This Winchester target brand delivers for me."

  • Click To Purchase This 5.56x45 Federal Ammunition
    based on the 2 reviews below
  • Chris said:

    "Not only is the price fantastic, but my shipment arrived in pristine condition. I was a new customer, and didn't know what to expect. I had a very bad experience buying ammunition on line from another place that claims to be 'cheaper than...ahem.. anything'. My experience with Ammo.com could not have been better. The trusted brand and quality of my order goes without saying. But the handling, packaging, and service from the people at Ammo.com was phenomenal, even surprising given the world we live in where poor service is pretty much expected. I will not shop anywhere else. Ammo.com is my go to supplier."

  • Tim said:

    "Good price for ammo, not shinny but who cares its ment to shoot not to look at "

  • Click To Purchase This 5.56x45 PMC Ammunition
    based on the 5 reviews below
  • txweld said:

    "All good"

  • Runner said:

    "PMC is a very reliable ammunition , I would not hesitate to use if for self defense. It shot well and now that I have shot it and used it all, I`ll need to order more. BTW , I use PMC in my handgun for home protection and it is as good as it gets and the 5.56x45 is as great . "

  • MM said:

    "I shot about 200 rounds through my brand new SIG716. The very first 3-4 rounds wouldn't feed perfectly, but I attribute this to the brand spanking new equipment. After that, rifle and ammo performed flawlessly. Not a single issue with feeding, cycling, firing, etc. At 150 yards, I had all shots within about 2-3 inches using a cheap scope and no rest. Great product and especially GREAT SERVICE! Thank you guys!!!"

  • D said:

    "Great customer service, placed the order last friday fully expecting not to get the order with all that is going on, you won't find a better company to deal with, as for the Ammo, top notch perfect for my use."

  • CowwFace said:

    "I got this for taking to the range, went through about 100 rounds and zero duds. works perfectly in 2 AR's. We were using Red-Dot scopes, and hit what we were aiming at about 100 yrds away. I would highly recommend this ammo."

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  • Click To Purchase This 5.56x45 PMC Ammunition
    based on the 5 reviews below
  • olbull said:

    "same as title"

  • john said:

    "good product / good price"

  • Snake said:

    "Great ammo! Shoots and cycles perfect. Will defiantly buy more. "

  • lroberts103 said:

    "Great company to work with. Fast shipping great price"

  • Michael said:

    "This 5.56 ammo was just what my AR needed."

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