The Mark-1 Project
The Mark-1 Project

5.56X45MM, 55GR, Mark-1 - 500CT

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5.56-BRASS-55GR-MK1-500
$28500
Out of stock

You will receive: 500 Rounds of 5.56 55GR FMJ Brass Casing  + Ammo Can 

Experience the pinnacle of ammunition craftsmanship with Mark-1's 5.56x45mm 55gr cartridges. Precision-engineered for unparalleled performance.

Caliber5.56x45mm NATO Casing MaterialBrass Muzzle EnergyApproximately 1 , 211.3 ft-lbs 1,211.3 ft-lbs for a 55gr bullet traveling at 3,109 fps. ft-lbs Muzzle VelocityApproximately 3,109 fps when fired from a 24-inch barrel. FPS Powder TypeBall Powder Primer TypeBOXER Bullet TypeFULL METAL JACKET (FMJ) Grain Weight55 GRAINS Package Dimensions11.5X7.25X5.06 inches Package Weight12.8 lbs Packaging TypeAmmo Can Round Count Per Package500 rounds

Featuring ARMSCOR BATCH: 

As Promised: Transitioning to Excellence As part of our unwavering commitment to quality, we've made a significant change: We've stopped using ZSR cases and have upgraded to premium ARMSCOR BATCH cases for our MARK-1 5.56 ammunition.

Mark-1 5.56x45mm 55GR Ammo a product of unmatched precision, consistency, and reliability. Crafted for professionals and shooting enthusiasts alike, each cartridge promises performance that stands a class apart. With a meticulous manufacturing process and rigorous quality checks, our 5.56x45mm ammunition redefines excellence in ballistics. Whether you're engaging in sharpshooting, tactical training, or recreational shooting, trust Mark-1 to deliver the perfect shot every time.

Ammo Specs
Caliber
5.56x45mm NATO
Casing Material
Brass
Muzzle Energy
Approximately 1 , 211.3 ft-lbs 1,211.3 ft-lbs for a 55gr bullet traveling at 3,109 fps.ft-lbs
Muzzle Velocity
Approximately 3,109 fps when fired from a 24-inch barrel. FPS
Powder Type
Ball Powder
Primer Type
BOXER
Bullet Type
FULL METAL JACKET (FMJ)
Grain Weight
55 GRAINS
Packaging Details
Package Dimensions
11.5X7.25X5.06inches
Package Weight
12.8 lbs
Packaging Type
  • Ammo Can
Round Count Per Package
500 rounds
Advanced Performance Metrics
Firearm Compatibility
Ensure your firearm is rated for 5.56mm before using it, AR-15/M16/M4 Platform Rifles, Ruger Mini-14, Steyr AUG, HK416, FN SCAR-L (MK 16), Sig Sauer SIG556, Tavor (IWI), CZ Bren 2, LWRC M6
Quality Assurance
Triple-checked using state-of-the-art technology to ensure each bullet meets our rigorous quality standards.
Precision/Accuracy
Expertly engineered for a balanced flight trajectory, our FMJ bullet maintains a true course to your target.
Flash
Minimized muzzle flash for discreet shooting, ideal for low-light conditions.
Feed
Optimized case and bullet design to ensure smooth feeding in semi-automatic firearms.
Consistency
Manufactured under tight tolerances to ensure uniformity across rounds, resulting in repeatable performance shot after shot.
Barrier Penetration
Solid FMJ construction designed to maintain integrity even when encountering barriers.
Recoil
Designed for a manageable and predictable recoil, enabling faster follow-up shots and improved shooting comfort.
5
5 out of 5
Reviews: 19
5 stars
100%
4 stars
0%
3 stars
0%
2 stars
0%
1 star
0%
Greg from NC
Verified purchase
5
What do you like about the product?
Excellent experience purchasing from Mark-1. I got the package in good time, and was pleased with the quality and was exactly as described. I haven't had a chance to try out the ammo yet, but will try to next weekend. I just felt compelled to leave a good review and will update but great job guys
What would you like us to improve?
Only a suggestion if you ever plan to offer 7.62 x 39 and 10mm in the future i'd be interested in purchasing!
Comment
Thanks also for the nice note was a cool touch
Mark-1 Team
We're so thrilled to hear about your excellent experience with us and that your package arrived safe and sound! It's great to know that everything was as expected, and we can't wait for you to try out the ammo. Fingers crossed for a fantastic range day next weekend! Thank you so much for taking the time to leave this awesome review; it genuinely means the world to us. We're always looking for ways to expand our offerings, so we'll definitely take your suggestion about stocking 7.62 x 39 and 10mm into consideration. Keep an eye out in the future! And you're very welcome for the note—we love adding that personal touch to show our appreciation for amazing customers like you. Looking forward to serving you again soon, and happy shooting! - The MARK-1 Ammo Team
Scott Watson
5
What do you like about the product?
Amazing product!!
What would you like us to improve?
Nothing. You have an amazing company.
Comment
Amazing company and customer service. The best company I’ve dealt with!!
Bradley
Verified purchase
5
What do you like about the product?
Like most folks, I was skeptical of a new brand, but Mark 1 made a great intro offer. I’m pleasantly surprised. After shooting about 100 rounds suppressed (RC2, 11.5” barrel), I found the ammo to be solid range plinking material. Will happily buy again around the same price or slightly higher.

I also found the customer service and the experience to be great — an ammo can, a handwritten thank you card, and a hat on the first order. These folks really seem to care, let’s hope that care and the quality holds up!
What would you like us to improve?
Only availability. Doing great!
Comment
Thanks, folks!
Jae Kim
Verified purchase
5
What do you like about the product?
All 500rds. shot flawlessly. No malfunction of any type.
What would you like us to improve?
Nothing
Comment
Bueno, 10/10. Look forward to trying to buy here first
Aaron
Verified purchase
5
What do you like about the product?
I love the product because the ammo shoots so well at a great price!! Super consistent with my shots at 100 Yards. Poa poi for me off a bench. It doesnt shoot very dirty for me, casings eject well!
What would you like us to improve?
The ammo, stickers, and ammo boxes are awesome and i have nothing negative to say. Only a suggestion to maybe have an option in the future where we can buy a box without the ammo if it saves us more money or lets you guys be able to pump out more ammo? Otherwise im going to find myself with a ton of ammo boxes, though thats not a total negative. I just wont have the room for them!
Comment
Keep up the awesome work. Your customer service is great, and you move a great product.
Rex
5
What do you like about the product?
Very happy with how quickly i received it at a good price in today's market. Ran about 50 rounds thru my AR with no issues. Researched manufacturer of 556 ammo and happy with what i read and reviews were very good to. Will definitely buy again
What would you like us to improve?
No problems with this company, will tell my friends about this ammo site.
Comment
This company ships to Massachusetts, getting harder to find ammo companies that will ship to this state. Thanks Mark1 ammo for what you do
Anonymous
5
What do you like about the product?
I can't say enough about this ammo. Ordered early Monday morning (3rd shift worker) and had the ammo at my door by Thursday afternoon. No issues out of the 300rds i put down range and good grouping.Hand written thank you note and a hat included. Those little things go a long way when common courtesy is lost today. Amazing customer service. I've already purchased several more of these cans and cases of 9mm. This company has a customer for life.
What would you like us to improve?
Nothing, keep pressing em so we can keep loading em
Comment
Can't beat price, quality, and amazing customer service!
Anonymous
5
What do you like about the product?
-Fast shipping
-Packaged well
-Very nice goodies and can
-Clean ammo like my booty
-Great website, and social media presence

What would you like us to improve?
I don't know.
Comment
I am very pleased that I took a chance on a new company. I hope Mark1Ammo continues to serve their customers and create a great community around their company and values. Thank you!
Justin v
5
What do you like about the product?
Excellent product!! Was afraid to try as anyone should be with a new business and I also couldn’t find allot of reputable positive reviews I spent almost an hour researching. Got my box in about 4 days with the hand written thank you not and upon close Inspection of ammo and putting it side by side with rounds from a very large trusted company mark1 took the win, excellent craftsmanship. I loaded up, pulled the trigger and to my relief it shot perfectly! All the scary thoughts of my gun cracking or blowing out from bad rounds went out the window I order another box that night!! No joke this is the only stuff I buy now especially because it small business American made
What would you like us to improve?
Maybe 1k rounds and up deals
Comment
Mark1,don’t lose sight of most of us work hard and want to spend our money on something that is of value and works when needed. If you keep the standard and the values I’ll keep buying
Anonymous
5
What do you like about the product?
The rounds I received were some of the best I've seen recently. Clean, consistent, reliable and accurate.
What would you like us to improve?
Some mark 1 merchandise and gear to proudly wear and use to show my support.
Comment
These guys aren't afraid to unashamedly stand for FREEDOM and that particular way of life and I will continue to use mark 1 as long as they do. The only thing better than the rounds they produce is the customer service they offer. Outstanding job gentlemen and keep up the good work! Stay FREE
Mark-1 Team
Heck yeah, brother!
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