According to STANAG 4172 and the official NATO proofing guidelines the 556 green tip 500 NATO case can
handle up to 420.0 MPa (60,916 psi) piezo service pressure. In NATO regulated organizations every rifle cartridge
combination has to be proofed at 537.5 MPa (77,958 psi) to certify for service issue.
STANAG 4172 defines the Belgian ball cartridge SS109 as the NATO reference cartridge and adds a
considerable number of technical requirements like a minimum pressure of 88.0 MPa (12,763 psi) at
the gas port 280 millimetres (11.0 in) down the 508 millimetres (20.0 in) long standard proof barrel and primer sensitivity that are not defined by civilian C.I.P. and SAAMI ammunition rulings and recommendations.
The NATOmilitary alliance uses a NATO-specific recognized class of procedures to control the
The civilian organisations C.I.P. and SAAMI use less comprehensive test procedures than NATO.
The NATO Manual of Proof and Inspection AC/225 (LG/3-SG/1) D/8 stipulates each weapon and
component considered vulnerable to the effects of a rapid change in pressure, for example barrels, breech blocks and bolts,
will be tested by firing one dry round at a corrected minimum of 25% over pressure and one oiled round at a
corrected minimum of 25% over pressure. Over pressure of 25% means 25% in excess of the service pressure
resulting for the 5.56×45mm NATO up to 430.0 MPa (62,366 psi) (Pmax) piezo service pressure.
The service pressure is defined as the mean pressure generated by the service cartridge at a temperature of 21 °C (70 °F).
Such a high pressure proof is conducted with both the weapon and ammunition conditioned to an ambient temperature of 21 °C (70 °F).
Each weapon will be individually tested, from an ammunition lot that produces a minimum corrected mean chamber pressure.
The corrected proof pressure requirement (service pressure (Pmax) + 25%) for the 5.56×45mm NATO like the STANAG 4172 is 537.3 MPa
(77,929 psi) (PE) piezo pressure. This pressure has to be recorded in a NATO-design EPVAT barrel with Kistler 6215 transducer,
HPI GP6 Transducer or by equipment to C.I.P. requirements.
The US SAAMI lists maximum average pressure (MAP) for the .223 Remington cartridge as 55,000 psi (379.2 MPa) piezo
pressure with deviation of up to 58,000 psi (399.9 MPa).
Whether you recently purchased your first AR platform rifle or have been shooting for quite some time,
chances are you have probably heard the phrase “green tip ammo.”
This popular 5.56 cartridge is also sometimes referred to as a “penetrator round” due to its 62-grain projectile,
partially steel core, and enhanced ability to punch through hard targets.
The official U.S. military designation for green-tipped 5.56 rounds is M855.
With ammo, the “M” usually stands for munitions, as the military likes to keep it simple.
Simplicity and creativity are two different things.
As with almost every weapon or cartridge, the military names is referred to by the letter “M” followed by a few numbers,
but that’s another conversation entirely.
Most of the information you will come across regarding green-tipped ammo is fairly accurate.
However, some popular misconceptions are still floating around.
To make things easier, we cut through all of the hype and get straight to the facts about the M855 cartridge.
Can I Legally Buy 556 Green Tip Ammo?
Currently, green-tipped ammo is legal for US civilians to own under federal law.
However, certain states, such as California, have Draconian gun laws that constantly seek to limit what state residents can own.
Due to these restrictions, it’s important to check up on the latest anti-gun laws in your home state before making a purchase.
The ATF and the federal government have made several attempts at banning the round in recent years.
Thankfully, these attempts to circumvent the second amendment have been met with minimal success.
The most recent attempt came on the heels of 2015 regulations that prohibited the use of lead ammunition on federal land.
These environmental restrictions have since been lifted.
Legislators did not specifically mention the M855 round in the 2015 legislation regarding lead.
However, the round does include a majority lead core and could not be used on these lands during the ban.
At around the same time, the ATF also attempted to assert that green tip ammo qualified as an “armor-piercing” round.
They argued that it should be banned under the 1985 Law Enforcement Officers Protection Act.
They cited that the round should no longer be granted a sporting exemption due to the rise in ownership of AR-pistols.
Fortunately, the M855 does not even meet their definition of “AP” ammo because the core is 80% lead.
The ATF shelved the pending ban after they received swift and overwhelming backlash, which included 53 U.S.
Senators and over 200 members of the U.S. House of Representatives.
The ATF definition of armor-piercing ammunition is posted below.
So, yes Virginia, you can still buy all the green tip rounds you can get your hands on.
18 USC 921(a)(17):
(B) The term “armor piercing ammunition” means—
(i) a projectile or projectile core which may be used in a handgun and which is constructed entirely (excluding the presence of traces of other substances) from one or a combination of tungsten alloys, steel, iron, brass, bronze, beryllium copper, or depleted uranium; or
(ii) a full jacketed projectile larger than .22 caliber designed and intended for use in a handgun and whose jacket has a weight of more than 25 percent of the total weight of the projectile.
M855 Versus M193
The M855 cartridge has a unique skill set, it works well with low twist rate rifle barrels and punches holes in things.
Even though they are no longer used by the U.S. Military, the civilian version of the M193 cartridge remains in continuous production by multiple manufacturers.
It’s still a popular alternative to the M855 on the civilian market.
The M193 cartridge contains a 55-grain boat-tail bullet that has a full copper jacket and a lead core.
The term “boat tail” simply refers to the shape of the bullet, which is intended to increase the range of the round.
We often get asked which of these two rounds is better, but the answer to that question depends on several factors.
If you just want to shoot paper or metal targets, M193 is your best bet.
If you hunt or plan on dropping a moving target at long-distances, the M193 wins again.
However, if you need to punch a hole in something, M855 is the best option. Since green-tipped ammo has a semi-steel core and is heavier than the M193, it’s better suited for certain applications.
Why Does Twist Rate Matter?
The twist rate of your rifle describes how drastic the turn of the rifling within your barrel is.
The twist rate is usually expressed as two numbers separated by a semi-colon such as 1:9. A barrel with this twist rate means
that the bullet will spin one revolution for every 9” of barrel length. The first number is always 1
and a lower second number equates to a faster twist rate.
Twist rates matter because they serve to stabilize the bullet. Heavier, longer bullets like those found in
green-tipped ammo need faster twist rates than the lighter M193 round. The M193 was designed
specifically for the Vietnam Era M16’s, which featured 20” barrels and slow twist rates of 1:12.
Picking a round suited for the rifle’s twist rate will lead to better results in terms of accuracy
. The best solution is to get your hands on a few different rounds with different weights and cores to see what gives you ideal results.
Since 5.56 rounds are worth their weight in gold at the moment, this is probably easier said than done.
To help your search, let’s consider 1:8 twist rates as our threshold. If your twist is 1:8 or faster, then green-tipped M855 is the way to go.
If your twist is slower, 62 grain is likely going to be as heavy as you want to go, and 55 grain will usually be ideal.
Remember, we are talking optimal performance at a distance as both rounds will be fine at 100 yards or less.
556 Green Tip Ammo Ballistics
In addition to performing better with certain twist rates, the ballistics of the M193 and M855 vary greatly.
The “softer” M193 projectiles do more ballistic damage when hitting soft targets, making them a good choice for hunting applications.
The M193 will fragment quite a bit and leave a huge wound cavity, especially inside of 100 yards.
You may be wondering why the M193 does so much more ballistic damage when the M855 has been dubbed “penetrator ammo.”
Well, this is because the lead-steel core and added grain weight of green-tipped ammo do their job a little too good at close ranges.
The M855 will usually punch clean through a target, doing minimal damage unless you hit a vital organ or important artery.
With shots over 100 yards, the ballistics comparison is a little more even. Once you surpass 300 yards, the green tips pull ahead.
I won’t bore you with a physics lesson, but it involves changes in the velocity of the bullet and angle of impact as the distance traveled increases.
M855 Ammo For Sale
If you’re looking online for green tip ammo, be sure to search for M855, SS109, and NATO keywords.
While I am a fan of green-tipped ammo and have a healthy supply in my safe, the M193 remains a more versatile round.
Using M855 as a self-defense round could lead to unwanted legal issues.
Imagine explaining to a judge how your penetrator bullets ended up in a neighbors fridge across the street.
The fact that M193 rounds break apart when hitting targets makes them the better choice for home defense.
If you’re looking for accuracy at distances and your rifle barrel has the appropriate twist rate, then keep some 62gr green tips on hand.
Being able to punch through a barrier without needing a larger cartridge does have its advantages.
Green-tipped ammo is a quality round that fires reliably and will not cause excess carbon build-up in your rifle like poorly made ammo.
When searching for green tip ammo, you’ll find a variety of options from companies such as Federal or PMC, who refer to this round as the XM855 and M855, respectively.
You may also come across foreign-made rounds that still use the SS109 designation or NATO round description.
Before buying, be sure to do your research. Carefully read the specs of the ammo, and make sure you are getting what you pay for.
IS GREEN TIPPED AMMO LEGAL?
The military designed green tip ammunition for maximum penetration. The government doesn’t classify the rounds as “armor piercing,” but they can deliver a powerful punch.
For this reason, many gun-control advocates have made attempts to stop the sale of these rounds.
Despite these efforts, green tipped ammo is legal to purchase and possess, although certain states have laws limiting who can own this type of cartridge.
(Check your state laws before making the purchase.)
GREEN TIPPED AMMO: A BALLISTICS BRIEFING
While ballistic stats such as velocity, energy, and trajectory can’t tell the entire story, they can help us understand the capability and performance of 5.56 green tipped rounds.
Especially how that performance compares to standard 55-grain FMJ rounds.
Only a few manufacturers make 5.56mm rounds that are painted green and classified as M855.
Other manufacturers may have 62-grain FMJ ammo in this cartridge, but they don’t qualify as M855 because they use a lead core and copper jacket instead of steel.
Winchester is probably the most common manufacturer of 5.56 green tipped ammo. Precision Made Cartridges (PMC) is another manufacturer, as is the Israeli Military Institute, or “IMI.”
Since the IMI does not have manufacturer’s statistics (that we can find), we’ll look at the listed stats for M855 ammo.
It is made by Winchester and PMC, and compare that to a sample of 55-grain FMJ rounds. It’s a small sample size.
It will help us understand the capability of green tipped ammunition.
VELOCITY
Muzzle (fps)
200 yards
400 yards
Winchester M855 Ammo
3,060
2,529
2,055
PMC M855 Ammo
3,100
2,449
1,885
Winchester 55-grain FMJ
3,180
2,425
1,943
PMC 55-grain FMJ
3,270
2,555
1,943
Federal 55-grain FMJ (American Eagle)
3,165
2,412
1,776
Hornady 55-grain FMJ (Frontier)
3,240
2,468
1,817
Judging by muzzle velocity, it appears the green-tipped ammo is a bit slower than many other rounds, but not by a significant margin. However, when the rounds start to approach 400 yards, they can be faster. This may be because the heavier round maintains momentum, allowing it to keep its speed at a greater distance.
Muzzle (ft-lbs)
200 yards
400 yards
Winchester M855 Ammo
1,289
800
581
PMC M855 Ammo
1,323
N/A
N/A
Winchester 55-grain FMJ
1,235
718
390
PMC 55-grain FMJ
1,306
N/A
N/A
Federal 55-grain FMJ (American Eagle)
1,223
711
385
Hornady 55-grain FMJ (Frontier)
1,282
744
403
These energy statistics bring a bit more clarity. It would be helpful to have downrange energy on PMC’s green tip ammo, but we can still look at Winchester’s for the comparison.
Muzzle energy is not outstanding. It’s higher than some, lower than others, but never far apart.
What is impressive is the energy at 400 yards. Winchester’s green tip ammo has an energy of 581 ft-lbs, while the rest hover around 400 ft-lbs.
This suggests that it may be more capable as a long-range hunting tool, especially if penetration is important.
TRAJECTORY
Trajectory may be the most difficult statistic to consider, mostly because manufacturers are inconsistent when providing these stats.
Let’s narrow our focus to the Winchester products, which provide information on rounds zeroed at 200 yards…
Drop at 300 yards
Drop at 400 yards
Drop at 500 yards
Winchester M855 Ammo
7.5 inches
22.9
49.4
Winchester 55-grain FMJ
9 inches
26.7 inches
55.3 inches
PMC provides information for cartridges zeroed to 100 yards…
Drop at 200 yards
Drop at 300 yards
Drop at 400 yards
PMC M855 Ammo
3.1 inches
11.9 inches
28.3 inches
PMC 55-grain FMJ
2.6
10.6
25.6
In these comparisons, we don’t see results that lead us to any specific conclusion. One green tip ammo (Winchester) drops less that its partnering round, the other (PMC) drops more. This seems to suggest that green tip ammo probably doesn’t offer any significant improvement in overall accuracy compared to other products. In other words, you wouldn’t buy this round simply for the superior trajectory.
SO…WHY GREEN TIPPED AMMO?
After all that, we come to the final thought: why purchase green tipped ammo?
Why purchase a non-expanding, heavier round that offers better downrange energy but doesn’t provide a significant improvement on velocity or trajectory?
For most hobby shooters, price is a big factor. Places like the Lake City Army Ammunition Plant make this ammunition large batches for military use.
While the military uses most of the rounds, there is often overstock. To reduce surplus ammo, Lake City sells the cartridges, often at a price much lower than average.
While green tipped ammo won’t be the lowest-cost 5.56x45mm round on the shelves, it’s certainly an affordable option.
The rounds are also effective for long-range target shooting and you can use them for long-range hunting in certain situations.
If you need penetration at a distance of 200, 300, or 400 yards, green tipped ammo may deliver quality results.
10 reviews for Buy 556 Green Tip Ammo Online | At Best Price
Rated 5 out of 5
Vanammo –
Very great ammo
Rated 5 out of 5
Vanammo –
wOW, so great content about 556 green tip ammo
Rated 5 out of 5
Vanammo –
I got my ammunition shipped on time
Rated 5 out of 5
Vanammo –
I really love this service, really like your customer service
Vanammo –
Very great ammo
Vanammo –
wOW, so great content about 556 green tip ammo
Vanammo –
I got my ammunition shipped on time
Vanammo –
I really love this service, really like your customer service
Vanammo –
got my ammo shipped on time
Vanammo –
i would buy this again
Vanammo –
stuff shoots so fast
Vanammo –
shoots so fast
Vanammo –
shoots so fast and accurate
Vanammo –
very accurate ammo