5.56 x 45 mm ammo

[WR Moore]

There's a lot of sea stories, war stories, myths & fairy tales about ammunition performance. No exception for the 5.56 x 45 mm round. If you read the Snopes decision it'll not only dismember a body, it'll shoot through buildings. I don't believe that, having burned a lot of it-mostly paid for by employers-but things do change and when I ran across some M855 green tip at a great price I grabbed a box.

I've got a post on here about Hornady Critical Defense and M193. I did the same water filled milk jugs and 4 layers of denim test with the M855 and duplicated the M193 results. 2 shattered jugs and calculated 5.8 inches of penetration. Hummm. The PMC website identified the bullet type as LAP, but didn't explain-either on the site or to an email- what that means.

If I'd have done the online research first, I'd have saved $13. There were several good links, but the best was to an NRA article. It covers a lot, including ammo types that actually are armor piercing. There's a discussion of why the cartridge has little effect on slightly built opponents. ETA: also notes that with 55 and 62 gr bullets, the 1-9 twist is more accurate than the 1- 7. https://www.americanrifleman.org/content/testing-the-army-s-m855a1-standard-ball-cartridge/

Short form: M855 is only a product improved M193. It has the same trajectory and uses the same sight settings as M193 but has only VERY slightly improved penetration capability on chance barriers. It replaced M193 (except possibly for some training) and the green painted tip only shows that it's not M193. After reading all this I expect the LAP acronym might mean "limited additional penetration".

M855A1 replaces M855 and is an other matter entirely. It has a bronze colored tungsten carbide penetrator tip separate from the jacket. It's intended to penetrate current body armor types. A quick check showed some advertised for sale......at about $3 a round plus shipping. I don't really see a personal need for any or for any M995 (black paint tip).

 

[bigggbbruce]

The PMC website identified the bullet type as LAP, but didn't explain-either on the site or to an email- what that means.

From ammo.com

"PMC X-TAC 5.56 NATO 62 grain LAP is PMC Ammunition's M855 or SS109 clone. Loaded with a 62-grain light armor piercing (LAP) bullet, this cartridge closely mimics the current issue green tip ammo for the U.S. military and its NATO allies. Like M855, these bullets have a mild steel core penetrator insert."

 

[Alk8944]

bigggbbruce beat me to it. LAP designates Light Armor Piercing. Since they are steel core bullets many ranges prohibit them, as well as being a fire hazard from sparks when shooting away from ranges.

 

[WR Moore]

OK, guys, let me quote from the linked article:

"Unlike the older bullet, the M855A1's penetrator is exposed, with a sharper tip, and it weighs 19 grains, nearly twice the weight of the M855's penetrator." The majority of the core of the M855 is lead, the penetrator is a segment in the tip of the bullet. There are cut aways that show that.

"According to the Army, the new (M855A1) bullet also penetrates concrete blocks at 90 yards when fired from an M16A2's 20-inch barrel, and at 40 yards when fired from an M4's shorter barrel. A single green-tip projectile could not breach a concrete block at any distance.

Because there were reported instances in Iraq of the older (M855) bullet failing to penetrate car doors or inflict serious wounds when fired into windshields, the new bullet was also tested according to FBI criteria against those prescribed barriers, including sheet steel and automobile glass. Not only did the M855A1 breach them, but it continued on into ballistic gelatin with sufficient weight and velocity to have inflicted serious or lethal wounds."

There were several references from ammunition sources that M855 is NOT classified as armor piercing. However, standards of what that means can change. The above quote doesn't seem to describe armor piercing capability if it won't go through a concrete block. Better barrier penetration than M193, yeah.

 

[bigggbbruce]

5.56x45 is ok, but my choice is 7.62x51.