Why Green Tip M855 is Not Armor Piercing

ITS Tactical discusses why the Steel Penetrator Tip of the M855/SS109 5.56x45mm NATO round does not make it legally a Armor Piercing (AP) round.

Bryan writes

Throughout my time in the Military, I’d always referred to M855/SS109 5.56 Ammunition (Green Tip) as armor piercing rounds or AP. For the life of me I can’t recall where I first heard that mentioned, but it was fairly common for it to be referred to as that.

Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


  • Interesting that folks thought green tip was AP, I’ve only ever heard ammo with black tips referred to as AP.

    Canada doesn’t have all the high speed, low drag kit though.

  • This has been common knowledge for years. I don’t know why it is all over blogs like breaking news. It use to be some of the cheapest stuff out there. Now it’s popular and more expensive. In the military using this stuff I’ve seen 2 rifles blown up by over pressure rounds. I have yet to see a rifle blown up with any other commercial ammo. With military training and private training I’m probabaly at 50/50 for rounds down range. I don’t shoot it for that reason. While no one was hurt, I just don’t want my rifle blown up. You can get better performance for cheaper out of other commercial ammo.

  • The article seems rather confused. He is confusing the issue of whether or not the ATF classifies the M855 as “armor piercing” under a statute that prohibits armor piercing handgun ammunition with the issue of whether or not a range would be happy to see you firing this round on their range.

    The legal definition is not relevant to whether or not a range would consider the round “AP” for range safety purposes.

  • Vitor

    What about the M855A1? It could steel at 450 meters that the old M855 could only penetrate at 200 meters.

  • Lance

    The reason why is mostly Military adopting the round as a standard antipersonnel round and to keep the steel core they drooped the AP reference.

  • jay1975

    I have been in the Army nearly two decades now and never once heard the green tips refered to anything other than ball ammo. We use green ball and orange tracer ammo and the tips tell us which is which. Regular units never carry armor piercing rounds for anything other than the .50 cal. The steel tip is a “green” bullet as it has no lead core and flies as far as the 7.62 due to the rotating steel tip. It was designed to increase accuracy at greater distances to overcome the 5.56’s shortcomings in Afghanistan.

  • Jeff
  • Jon

    SS109 is referred to as deep penetrator, only the black tip is classified as AP. Though AP is made in 556, I have only seen it fielded in 308 and larger calibers.

  • Sid

    I can’t speak intellegently about travel habits of PFC Santiago. COL Jessup

    As for the US Army, the green tip was NEVER classified as AP. In 1987, we switched to the M16A2. Though keeping the same caliber, the A2 fires a completely different bullet. Both casing and bullet are heavier. It is also why the twist rate went from 1:9 to 1:7. Stabilizing a heavier bullet was accomplished with a faster twist.

    The M16A1 can fire the A2 bullet but not as accurately because of the slower twist. The A2 cannot fire the A1 ammo because we learned very quickly that the casing would rupture and the twist-rate bullet did not work. I saw very frequently that the newer bolts would tear an A1 casing.

    So, the bullets were color-coded until we burnt up the A1 ammo. Ball ammo is green. Tracers are orange. AP bullets have a black tip. And so and so forth. The green tip has not been dropped because we continue to color code our bullets. Last deployment, we even got some Mk262s and not only were the bullets color-coded but I had my ACOG equipped designated marksmen color-code the magazines as a backup control measure.

    The green paint does not enhance the performance of the bullet, either. I have tried rainbow color schemes and smiley faces using high-heat engine paint. I don’t know if the wounds were more humane, but I did seem to feel better shooting it.

  • Lance


    You can fire M-193 ball ammo or you called it A1 ammo in a A2. There is nothing to due with the case or rupturing. Ive shoot M-193 ammo in a A2 and so has local USCG unit Ive seen shoot A1 ammo in M-16A2s. The 1 in 7 twist can handle lighter 55gr bullets but not lighter than 52gr varmint bullets. but it’ll handle all military ammo fine.

    The A1 did NOT have a 1 in 9 twist but a 1 in 12 twist. It can’t handle M-855 or M-855A1 ammo because its slower twist makes the bullet keyhole and you cant even hit a target a 50yards doing this.

    As per color M-193 ammo had no clor telling troops it was 55gr ammo the Green tip is 62gr and while it had a AP core the whole military categorized it as ball so no issue with politicians arose. AP or Black tip (in some cases they where painted blue) was never issued outside of test or SOCOM usage.

    Mk-262 has no color because it’s HP bullets hole can easily identify the round.

  • mike

    i have 556 GreenTIPS that have ad on the bottom and red paint on the primer ware are they from