5.56x45 Ammo

Used in the M4 series of rifles and other military style rifles, the 5.56x45 is a hugely popular cartridge.  Besides military uses it is commonly used in competition firearms, home defence applications it is replacing shotguns in many police cruisers. Learn More
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  1. Winchester 5.56x45 Ammo - 20 Rounds of 55 Grain FMJ Ammunition

    85 In stock now

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    Image For 20 Rounds Of 55 Grain FMJ Boxer Brass 5.56x45 Winchester Ammunition
    $7.99 Price

    Qty:

    • 20 Rounds
    • Made by Winchester

    • New Condition
    • 20 Rounds
    • Made by Winchester
    • American-made Discount Range
    • 40¢ Cost Per Round
    • Winchester SKU Q3131
    • UPC 020892201880
  2. PMC 5.56x45 Ammo - 20 Rounds of 55 Grain FMJ Ammunition

    79 In stock now
    Image For 20 Rounds Of 55 Grain FMJ-BT Boxer Brass 5.56x45 PMC Ammunition
    $8.25 Price

    Qty:

    • 20 Rounds
    • Made by PMC

    • New Condition
    • 20 Rounds
    • Made by PMC
    • Foreign Discount Range
    • 41.3¢ Cost Per Round
    • PMC SKU 5.56X
    • UPC 741569010115
  3. PMC 5.56x45 Ammo - 20 Rounds of 62 Grain FMJ Ammunition

    86 In stock now
    Image For 20 Rounds Of 62 Grain FMJ Boxer Brass 5.56x45 PMC Ammunition
    $8.75 Price

    Qty:

    • 20 Rounds
    • Made by PMC

    • New Condition
    • 20 Rounds
    • Made by PMC
    • Foreign Discount Range
    • 43.8¢ Cost Per Round
    • PMC SKU 5.56K
    • UPC 741569010122
  4. Prvi Partizan 5.56x45 Ammo - 20 Rounds of 55 Grain FMJ-BT Ammunition

    82 In stock now

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    Image For 20 Rounds Of 55 Grain FMJ-BT Boxer Brass 5.56x45 Prvi Partizan Ammunition
    $8.99 Price

    Qty:

    • 20 Rounds
    • Made by Prvi Partizan

    • New Condition
    • 20 Rounds
    • Made by Prvi Partizan
    • Foreign Discount Range
    • 45¢ Cost Per Round
    • Prvi Partizan SKU PP5.21
    • UPC 8605003807971
  5. Federal 5.56x45 Ammo - 20 Rounds of 55 Grain FMJ-BT Ammunition

    72 In stock now

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    Image For 20 Rounds Of 55 Grain FMJ-BT Boxer Brass 5.56x45 Federal Ammunition
    $9.19 Price
    • $8.85 each if you buy 5 -  save 4%
    • $8.75 each if you buy 10 -  save 5%

    Qty:

    • 20 Rounds
    • Made by Federal

    • New Condition
    • 20 Rounds
    • Made by Federal
    • American-made Range
    • 43.8¢ to 46¢ Cost Per Round
    • Federal SKU XM193
    • UPC 029465094607
  6. Winchester 5.56x45 Ammo - 20 Rounds of 62 Grain FMJ Ammunition

    21 In stock now

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    Image For 20 Rounds Of 62 Grain FMJ Boxer Brass 5.56x45 Winchester Ammunition
    $9.99 Price

    Qty:

    • 20 Rounds
    • Made by Winchester

    • New Condition
    • 20 Rounds
    • Made by Winchester
    • American-made Range
    • 50¢ Cost Per Round
    • Winchester SKU Q3269
    • UPC 020892213371
  7. Winchester 5.56x45 Ammo - 20 Rounds of 50 Grain Frang. Ammunition

    74 In stock now

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    Image For 20 Rounds Of 50 Grain Frang. Boxer Brass 5.56x45 Winchester Ammunition
    $12.00 Price

    Qty:

    • 20 Rounds
    • Made by Winchester

    • New Condition
    • 20 Rounds
    • Made by Winchester
    • American-made Range
    • 60¢ Cost Per Round
    • Winchester SKU USA556JF
    • UPC 020892219816
  8. Hornady Superformance Match 5.56x45 Ammo - 20 Rounds of 75 Grain HPBT Ammunition

    62 In stock now

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    Image For 20 Rounds Of 75 Grain HPBT Boxer Brass 5.56x45 Hornady Ammunition
    $19.99 Price

    Qty:

    • 20 Rounds
    • Made by Hornady

    • New Condition
    • 20 Rounds
    • Made by Hornady
    • American-made Range
    • 100¢ to $1.00 Cost Per Round
    • Hornady SKU 81264
    • UPC 090255812640
  9. Winchester Super Clean 5.56x45 Ammo - 20 Rounds of 55 Grain JSP Ammunition

    17 In stock now

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    Image For 20 Rounds Of 55 Grain JSP Boxer Brass 5.56x45 Winchester Ammunition
    $22.99 Price

    Qty:

    • 20 Rounds
    • Made by Winchester

    • New Condition
    • 20 Rounds
    • Made by Winchester
    • American-made Range
    • $1.15 Cost Per Round
    • Winchester SKU SC556NT
    • UPC 020892211254
  10. Hornady 5.56x45 Ammo - 20 Rounds of 55 Grain GMX Ammunition

    35 In stock now

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    Image For 20 Rounds Of 55 Grain GMX Boxer Brass 5.56x45 Hornady Ammunition
    $24.00 Price

    Qty:

    • 20 Rounds
    • Made by Hornady

    • New Condition
    • 20 Rounds
    • Made by Hornady
    • American-made Range
    • $1.20 Cost Per Round
    • Hornady SKU 81254
    • UPC 090255812541
  11. Winchester 5.56x45 Ammo - 20 Rounds of 77 Grain HPBT Ammunition

    63 In stock now

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    Image For 20 Rounds Of 77 Grain HPBT Boxer Brass 5.56x45 Winchester Ammunition
    $24.99 Price

    Qty:

    • 20 Rounds
    • Made by Winchester

    • New Condition
    • 20 Rounds
    • Made by Winchester
    • American-made Range
    • $1.25 Cost Per Round
    • Winchester SKU S556M
    • UPC 020892220379
  12. Black Hills Ammunition 5.56x45 Ammo - 50 Rounds of 69 Grain OTM Ammunition

    28 In stock now
    Image For 50 Rounds Of 69 Grain OTM Boxer Brass 5.56x45 Black Hills Ammunition Ammunition
    $46.99 Price

    Qty:

    • 50 Rounds
    • Made by Black Hills Ammunition

    • New Condition
    • 50 Rounds
    • Made by Black Hills Ammunition
    • American-made Range
    • 94¢ Cost Per Round
    • Black Hills Ammunition SKU D556N12
    • UPC 612710127405
  13. Black Hills Ammunition 5.56x45 Ammo - 50 Rounds of 77 Grain OTM Ammunition

    60 In stock now
    Image For 50 Rounds Of 77 Grain OTM Boxer Brass 5.56x45 Black Hills Ammunition Ammunition
    $49.00 Price

    Qty:

    • 50 Rounds
    • Made by Black Hills Ammunition

    • New Condition
    • 50 Rounds
    • Made by Black Hills Ammunition
    • American-made Range
    • 98¢ Cost Per Round
    • Black Hills Ammunition SKU D556N9
    • UPC 612710126408
  14. Federal American Eagle 5.56x45 Ammo - 150 Rounds of 55 Grain FMJ Ammunition

    43 In stock now

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    Image For 150 Rounds Of 55 Grain FMJ Boxer Brass 5.56x45 Federal Ammunition
    $65.00 Price

    Qty:

    • 150 Rounds
    • Made by Federal

    • New Condition
    • 150 Rounds
    • Made by Federal
    • American-made Discount Range
    • 43.3¢ Cost Per Round
    • Federal SKU XM193BK150
    • UPC 029465065225
  15. Black Hills Ammunition 5.56 Ammo - 50 Rounds of 62 Grain Barnes TSX Ammunition

    9 In stock now

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    Image For 50 Rounds Of 62 Grain TSX Boxer Brass 5.56x45 Black Hills Ammunition Ammunition
    $72.00 Price

    Qty:

    • 50 Rounds
    • Made by Black Hills Ammunition

    • New Condition
    • 50 Rounds
    • Made by Black Hills Ammunition
    • American-made Hunting
    • $1.44 Cost Per Round
    • Black Hills Ammunition SKU D556N18
    • UPC 612710129621
  16. Federal 5.56x45 Ammo - 120 Rounds of 62 Grain FMJ Ammunition

    90 In stock now

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    Image For 120 Rounds Of 62 Grain FMJ Boxer Brass 5.56x45 Federal Ammunition
    $72.99 Price

    Qty:

    • 120 Rounds
    • Made by Federal

    • New Condition
    • 120 Rounds
    • Made by Federal
    • American-made Discount Range
    • 60.8¢ Cost Per Round
    • Federal SKU XM855 LPC120
    • UPC 029465065102
  17. Federal 5.56x45 Ammo - 150 Rounds of 62 Grain FMJ Ammunition

    88 In stock now

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    Image For 150 Rounds Of 62 Grain FMJ Boxer Brass 5.56x45 Federal Ammunition
    $77.00 Price

    Qty:

    • 150 Rounds
    • Made by Federal

    • New Condition
    • 150 Rounds
    • Made by Federal
    • American-made Discount Range
    • 51.3¢ Cost Per Round
    • Federal SKU XM855BK150
    • UPC 029465065164
  18. Prvi Partizan 5.56x45 Ammo - 200 Rounds of 55 Grain FMJ-BT Ammunition

    27 In stock now

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    Image For 200 Rounds Of 55 Grain FMJ-BT Boxer Brass 5.56x45 Prvi Partizan Ammunition
    $90.00 Price

    Qty:

    • 200 Rounds
    • Made by Prvi Partizan

    • New Condition
    • 200 Rounds
    • Made by Prvi Partizan
    • Foreign Discount Range
    • 45¢ Cost Per Round
    • Prvi Partizan SKU PP5.3
    • UPC 8605003807179
  19. Federal 5.56x45 Ammo - 500 Rounds of 55 Grain FMJ-BT Ammunition

    56 In stock now

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    Image For 500 Rounds Of 55 Grain FMJ-BT Boxer Brass 5.56x45 Federal Ammunition
    $199.99 Price

    Qty:

    • 500 Rounds
    • Made by Federal

    • New Condition
    • 500 Rounds
    • Made by Federal
    • American-made Discount Range
    • 40¢ Cost Per Round
    • Federal SKU XM193
    • UPC 50029465094602
  20. Federal 5.56x45 Ammo - 420 Rounds of 55 Grain FMJ-BT Ammunition

    61 In stock now

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    Image For 420 Rounds Of 55 Grain FMJ-BT Boxer Brass 5.56x45 Federal Ammunition
    $199.99 Price

    Qty:

    • 420 Rounds
    • Made by Federal

    • New Condition
    • 420 Rounds
    • Made by Federal
    • American-made Range
    • 47.6¢ Cost Per Round
    • Federal SKU XM193LC1 AC1
    • UPC 50029465065206
  21. Federal M855 5.56x45 Ammo - 420 Round Stripper Clips 62 Grain FMJ Ammunition

    55 In stock now
    Image For 420 Rounds Of 62 Grain FMJ Boxer Brass 5.56x45 Federal Ammunition
    $235.00 Price

    Qty:

    • 420 Rounds
    • Made by Federal

    • New Condition
    • 420 Rounds
    • Made by Federal
    • American-made Range
    • 56¢ Cost Per Round
    • Federal SKU XM855LC1 AC1
    • UPC 50029465063189
  22. Federal American Eagle 5.56x45 Ammo - 600 Rounds of 55 Grain FMJ Ammunition

    57 In stock now

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    Image For 600 Rounds Of 55 Grain FMJ Boxer Brass 5.56x45 Federal Ammunition
    $240.00 Price

    Qty:

    • 600 Rounds
    • Made by Federal

    • New Condition
    • 600 Rounds
    • Made by Federal
    • American-made Discount Range
    • 40¢ Cost Per Round
    • Federal SKU XM193BK150
    • UPC 50029465065220
  23. Federal 5.56x45 Ammo - 600 Rounds of 62 Grain FMJ Ammunition

    67 In stock now

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    Image For 600 Rounds Of 62 Grain FMJ Boxer Brass 5.56x45 Federal Ammunition
    $285.00 Price

    Qty:

    • 600 Rounds
    • Made by Federal

    • New Condition
    • 600 Rounds
    • Made by Federal
    • American-made Range
    • 47.5¢ Cost Per Round
    • Federal SKU XM855BK150
    • UPC 50029465065169
  24. Federal 5.56x45 Ammo - 600 Rounds of 62 Grain FMJ Ammunition

    52 In stock now

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    Image For 600 Rounds Of 62 Grain FMJ Boxer Brass 5.56x45 Federal Ammunition
    $299.95 Price

    Qty:

    • 600 Rounds
    • Made by Federal

    • New Condition
    • 600 Rounds
    • Made by Federal
    • American-made Discount Range
    • 50¢ Cost Per Round
    • Federal SKU XM855 LPC120
    • UPC 50029465065107
  25. Prvi Partizan 5.56x45mm Ammo - 1000 Rounds of 55 Grain FMJ Ammunition

    27 In stock now
    Image For 1000 Rounds Of 55 Grain FMJ Boxer Brass 5.56x45 Prvi Partizan Ammunition
    $349.99 Price

    Qty:

    • 1000 Rounds
    • Made by Prvi Partizan

    • New Condition
    • 1000 Rounds
    • Made by Prvi Partizan
    • Foreign Discount Range
    • 35¢ Cost Per Round
    • Prvi Partizan SKU PP5.21
    • UPC 8605003807971C
  26. PMC 5.56x45 Ammo - 1000 Rounds of 55 Grain FMJ Ammunition

    59 In stock now
    Image For 1000 Rounds Of 55 Grain FMJ-BT Boxer Brass 5.56x45 PMC Ammunition

    Price $380.00

    Price $349.99

    Qty:

    • 1000 Rounds
    • Made by PMC

    • New Condition
    • 1000 Rounds
    • Made by PMC
    • Foreign Discount Range
    • 35¢ Cost Per Round
    • PMC SKU 5.56X
    • UPC 20741569010119
  27. PMC 5.56x45 Ammo - 1000 Rounds of 62 Grain FMJ Ammunition

    63 In stock now
    Image For 1000 Rounds Of 62 Grain FMJ Boxer Brass 5.56x45 PMC Ammunition

    Price $430.99

    Price $389.99

    Qty:

    • 1000 Rounds
    • Made by PMC

    • New Condition
    • 1000 Rounds
    • Made by PMC
    • Foreign Discount Range
    • 39¢ Cost Per Round
    • PMC SKU 5.56K
    • UPC 20741569010126
  28. Winchester 5.56x45 Ammo - 1000 Rounds of 55 Grain FMJ Ammunition

    56 In stock now

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    Image For 1000 Rounds Of 55 Grain FMJ Boxer Brass 5.56x45 Winchester Ammunition
    $400.00 Price

    Qty:

    • 1000 Rounds
    • Made by Winchester

    • New Condition
    • 1000 Rounds
    • Made by Winchester
    • American-made Discount Range
    • 40¢ Cost Per Round
    • Winchester SKU Q3131
    • UPC 50020892201885
  29. Lake City 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 Federal Ammunition
    $419.99 Price

    Qty:

    • 1000 Rounds
    • Made by Federal

    • New Condition
    • 1000 Rounds
    • Made by Federal
    • American-made Range
    • 42¢ Cost Per Round
    • Federal SKU XM855CS
    • UPC 029465065010
  30. Federal 5.56x45 Ammo - 900 Rounds of 62 Grain FMJ M855 Ammunition

    63 In stock now

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    Image For 900 Rounds Of 62 Grain FMJ Boxer Brass 5.56x45 Federal Ammunition
    $429.99 Price

    Qty:

    • 900 Rounds
    • Made by Federal

    • New Condition
    • 900 Rounds
    • Made by Federal
    • American-made Discount Range
    • 47.8¢ Cost Per Round
    • Federal SKU ZSAM855MOD
    • UPC ZSAM855MOD900
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  • Click To Purchase This 5.56x45 Federal Ammunition
    based on the 16 reviews below
  • Joe said:

    "I am very pleased with their service, quick delivery and product. I have not experienced any issue with their product at the range. I highly recommend this website for all the above mentioned reasons."

  • A65impalla said:

    "I was glad to find that Ammo.com had plenty of stock of this ammo. I searched the net of a lot of places, their prices are very competitive."

  • twolazy said:

    "I have not shot any of this batch or the batch prior, I haven’t even opened the boxes. I’m in high hopes I never have to open these boxes. I’ve used Federal 5.56 before and it is good stuff. Price is stiff, not as stiff as some I’ve seen. But then everything gun related is more expensive, isn’t it. Get it while the getting is good."

  • Doc said:

    "I guess a shortage in the ammo supply has driven the price up, as I found your ammo to be a bit more expensive than I had anticipated.. Regardless, the delivery time was exceptional & the ammo itself came in good condition and preformed well."

  • Tommy said:

    "I have already recommended it, that being said, it is a bit pricey. But considering that there is such a shortage, I was happy to have it. I get a small disability check once a month, so, I'll have to save more money."

  • CJ said:

    "The order was handled quickly and efficiently. I would recommend Ammo.com to anyone who has stood in line trying to find ammo."

  • Adam said:

    "Good, Clean, ammo....pricey but what can ya do....fast delivery too I cant even find a die set to reload let alone the bullets or primers so this ammo will do untill times are better....if ever "

  • deaves1 said:

    "5 stars"

  • Don said:

    "Nice to know where to locate ammo after this BS of low production and high demand."

  • Joe-we-had-a-baby-it's-a-boy said:

    "Ammo was well packed, but the tins came in a bit banged up. Ammo was clean in good shape but stripper clips showed moisture damage with minor rust making it hard to load with the speed loader. The cost was deffently high and go figure right after I ordered I found 1000rnds of loose pack 62gr lake city for the same price as one tin of 420rnds, but finding 556 ammo these days is deffently a gamble of finding it and its price! Hopefully all this Bull will be over soon!"

  • mrob6868 said:

    "Good and clean, but a little pricey."

  • nikpac said:

    "good clean ammo and a great overall value"

  • trooper said:

    "This ammo package is over twice as expensive as it should be. If you don't reload your own .223 just go with Wolf... "

  • jj said:

    "a good qalityt shell cida "

  • Gilbert said:

    "good"

  • Gilbert said:

    "good clean ammo sum what pricey but good over all"

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  • 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 Federal Ammunition
    based on the 4 reviews below
  • gokart04 said:

    "Finally got to shoot some of this the other day. Worked well and shot consistant/accurate. No feeding or fire failures out of about 100 rounds in my BCM AR-15. I feel the price is a bit too high at this time. "

  • J.W. said:

    "These were the first rounds shot through my ar. I have no complaints, it cycles fine even through rapid firing. I would definitely buy these again."

  • H.D. said:

    "Works great, cycles fine, glad I found your sight."

  • Pat said:

    "This is excellent ammo. Velocity is up there, at least in my 20" barrel DTI ar 15. Kinda lucky to buy this cheap ammo and get it to shoot the way this stuff did. I love being able to buy metal cases as well as brass cases. The metal are non-reloadable and it's nice to just shoot these and not worry about looking after shooting. I worry about the future of buying ammo over the 'net in the future. Here in Illinois our great governor Quinn moves on every front to close the avenues to get ammo. Good Shooting to All "

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  • Click To Purchase This 5.56x45 Prvi Partizan Ammunition
    based on the 3 reviews below
  • GearheadTony said:

    "I have tried several more expensive brands of 5.56 and .223, but none of them can match the performance per dollar of PRVI. This is now the only ammo I use in my AR. As for Lewmed's review above, my 16" AR with my not-so-steady trigger finger are able to make 2MOA groups at 100 yards. 4 to 5 inches?!?! Not in my rifle."

  • Lewmed said:

    " This is nice clean ammo that shoots and works in all 3 of my AR'S but it is not as accurate as mil. spec. ammo like lake city M193 My normal 21/2" 100 yard groups open up to 4 to 5" I'll use it for 50 yard range ammo."

  • Dorothy said:

    "Thought it wouldn't hurt to give it a shot. I was right."

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

    "62 grain shoots just fine. no jams. but that old vietnam ak will fire, even when dropped in mud, and water. thanks Im just glad you had the ammo, and the price was right."

  • Mikey A said:

    "As usual very prompt customer service and worry free shipping, love these guys & gals @ ammo.com. Well I am no expert about ammo, but I will say that this ammo was performing better than some more expensive products. fresh and snappy, good penetration and groupings 2"-3" @ 200-300 yds, mini-14 1-9 twist , similar to SS109 m855 but heavier Gr. "

  • 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 PMC Ammunition
    based on the 2 reviews below
  • Nate said:

    "The ammo itself LOOKS beautiful compared to Lake City penetrators but I have not shot it yet so I can't comment on that. I paid more per round, but that is just the market, not Ammo.com."

  • Bigthiss said:

    "Great ammunition for the price. I used to buy the federal loose bulk ammo in 500 and 1000 but there were always at least 10-20 that were either faulty loads or misfired. This ammo is hands down the best for the price that I have purchased and shot. Highly recommend!! "

The 5.56x45 cartridge was developed after extensive research into small caliber, high-velocity (SCHV) projectiles in the late 1950's and early 1960's and became one of the most popular centerfire cartridges in the world. Law enforcement agencies and militaries around the world use the cartridge, as do an increasing number of civilians in the United States. The .223 Remington is a sister cartridge that was inspired by the 5.56x45, and it can be fired from rifles chambered for the 5.56 (but for safety's sake, not the other way around).

The 5.56x45 was first loaded with full metal jacket bullets weighing 55 grains that exited the barrel of the new AR-15 rifle at more than 3,200 feet per second. The AR-15 eventually became the M16. Since then, many different projectiles have capped this cartridge, including the M855 - a steel penetrator tip, and the Mk318 - a barrier-blind. Both of these bullets weigh 62 grains. For precision marksmanship, the 5.56 cartridge uses a Sierra MatchKing 77 grain Boat Tail Hollow Point, or the Mk262 Open Tip Match bullet.

Popular worldwide, many manufacturers of firearms have produced weapons chambered for the 5.56x45 cartridge. Armalite, Bushmaster, Colt and others have manufactured semi-automatic rifles and fully automatic rifles chambered in 5.56x45.