Saw this written up in Wikipedia:

Mk318

Following early engagements in Afghanistan and Iraq, U.S. Special Operations Forces reported that M855 ammunition used in M4A1 rifles was ineffective. In 2005, the Pentagon issued a formal request to the ammunition industry for “enhanced” ammunition. The only business that responded was the Federal Cartridge Company, owned by Alliant Techsystems.  The first prototype rounds were delivered to the government in August 2007. But even these rounds have less than stellar performance.




OK, so this confirms what I have thought for a long time i.e. the M4 has been castrated in effectiveness (just like our military with ROE). When you shorten the barrel and increase the weight of the bullet you have just about eliminated the reason why the 5.56 round was so effective in Vietnam. I say increase the barrel length back to 20 inches, slow down the rifling to 1:12 or 1:14, decrease the bullet weight to 50 or 55 grains, and try to keep the velocity as high as possible. My A1, like the one shown in the picture above, has a 1:12 barrel and I shoot 50Gr soft-points at 3400. You don't want to see what this does to coyotes., but it would be devastating on humans. Mostly one shot kills in my estimation. Hey, if you are going to go to war you may as well be prepared.

Faster, lighter projectiles with just enough spin to stabilize them on the way to the target has always been a damn good way to create some nasty wounds.

I saw the effect of the M855 in Afghanistan first hand and unless you hit a major bone like the pelvis or femur, it would just create an "ice pick" wound channel. After a few engagements, we just started aiming for to the pelvic girdle instead of center mass. Lots of factors come into play too. For the most part the people we are shooting over there are smaller and skinnier. The M855 sucks when you need a very shallow penetration in very thin people. The M855 does not begin to fragment until 10" or so, IIRC. Couple that with the 14" barrel on the M-4 and you take a lot of that speed needed for fragmentation.

We should just go back to the M193 and tailor the load to whatever length barrel is predominantly being used.

I recall reading testimony from the Mai Lai Massacre about the M193 and the M16,
and the 'ethics' of a 'dum dum' round in war.  Citing the lethality and trauma damage to
the civilians murdered by Lt. Calley & his men (to which it should be noted they were
victims of the system and possibly from the nerotoxins of Agent Orange in their water.)

Stoner had concluded, the optimum length vs. velocity for the 222 special was 18.5"
for the barrel.  I think the army got the extra 1.5" for bayonet installation.

For the purposes intended, the M16A1 is overall the better weapon, a 300 meter or less rifle.

Its always been my understanding that the problem with the M855 in combat was that the bullet wouldn't  fragment until after it had left traveled through the body so damage was minimal.

Speed kills or at least aids in it.  Longer barrel, lighter projectile, high speed . The entire 5.56 platform is predicated on speed in order to do damage.

In Afghanistan we got a bunch of EBR's after the first 5 months at Gormach. M4's suck for anything other than CQB, even with M855A1 imo. (we had it on our deployment)

ETA: Thank goodness as civilians can load their magazines with better ammunition for defensive & hunting purposes. Though, I have both 20" and pinned 14.5"

Consider that the M193 55 grain from a 20" barreled M16A1 travels at 3300 FPS, and is still faster at 200 yards than the 2500-2600 fps needed to reliably yaw and fragment (the main mechanism for grievous wounding).  The M855 from a 14.5 inch barrel barely breaks 2750 FPS at the muzzle and drops below the 2500-2600 FPS at 75 yards.  I have seen hits from M193 in my LEO career, and I'll just say they are NASTY!  The early 1/14 twist barrels were only marginally stable (like 5.45x39 7N6), and they really made bad wounds.

At close range, the M193 even surpasses the MK262 MOD1 77 grainers.  past 100 yards, the MK262 surpasses, but under 100 yards, it is hard to beat M193.  It was this reminiscing about what I have seen, and re-defining how I intend to use my KISS Carbine that made me decide to sell off my MK262 and M855 ammo to fund the project.

Great video, Thanks!  I am happy to have 1,200 rounds of Federal/Lake City M193, and the components to cook up another 600-700 on my reloader using 25 grains of IMR 4064, of which I have several pounds.

Just got back from the range. Tried some new loads in the A1 to see what speed I could get out of some new bullets. The loads were 50gr ballistics tips and some surplus 55gr soft points from Winchester. The 50gr's clocked at 3300 and the 55gr's clocked at 3250. The load for both was 30gr of BL(C)2. The powder charge came up to the bottom of the neck so it was a slightly compressed load for both the 50 and 55gr's. A buddy was saying to just dip the cases in the powder and then scrape off excess so the powder is level with the case mouth but haven't tried that so far. Hunted with  .22-260 doing 3600 with a Sierra 55gr SBT (#1365) for years and it was a one shot killer pretty much no matter where you hit em' (coyotes). Agreed that the 5.56 is a close in round - maybe 200 yards or so is perfect. Longer than that and you're probly better off with a bolt gun. Just bugs me to no end we go with short barrels and heavy bullets and then wonder why can't efficiently kill the rag heads.

55gr vmax

From the Wikipedia article entitled "M16 rifle" under the "terminal ballistics" section:

Any questions?

Red

+1

I may not have a retro AR15 at the moment but I use retro ammo.

I have been telling guys on a few other forums about the effects of M193 on human tissue, especially in CQB usage. SO many are hyped up on the Mk262 or M855 for close distances. They fail to recognize the attributes of the M193 round. Personally, for defensive purposes, I still prefer and recommend the M193. For other types of engagements, the M855 and Mk262 has it benefits.

I agree. MK262 is great at 300 yards, but is no better at 75 to 100. I have never been a fan of M855 as I thought it was a step in the wrong direction. I only had 300 rounds of it.

I just love the statements about the early M16 being an inhumane weapon. What a crock. I can toss a grenade at you and fragment your body and that is not inhumane? I mean, when it comes to war what the hell are these guys talking about? War is hell and that's why you never want to get into one. But if you are gonna force me into a war then I want a rifle that will kill efficiently like my 22-250 kills - one shot killer with the Sierra 55Gr SBT #1365. I've taken Mule Deer, Antelope, Coyote, Grey Fox, Bobcat, Mt Lion, Badger, etc and this thing kills like the wrath of God....even with marginal hits. If you're gonna send me up against a bunch of screaming ragheads then I'm gonna stop that screaming in microseconds with a round that'll DO SOMETHING! To me that means at least 3400FPS even if I have to step down to a 50Gr slug to get that speed. That's what the original M16 was all about = small bullet going fast to let not only the bullet frag and do damage but to let copious levels of hydrostatic shock travel along the major arteries right to the brain and put the light out at the speed of sound...... All this politically correct crap is getting our guys killed the way I figure it.

This!

I killed 29 dogs of varying sizes in Iraq, using a 14.5" (1/9) Bushmaster barreled M4. Most were shot with issued 62gr and made a .22 caliber hole in and out. Had to shoot them in the shoulder to drop them and then run up and shoot them in the head. I killed 15 with MK262 and all were one shot one kill. None exited the carcass, dumping all the energy in the body. Very effective combination.

Longest shot was 175 meters on a 150lb dog. Sucker was huge.

Which is why the M855 sucks on tissue. It will not do any good unless you hit a major bone. It passes right though soft tissue and will not transfer any energy to the target. It is decent at penetrating armor but that is about it. I saw Taliban shrugging off hits from M855. Most of those hits were to the abdomen and soft tissue. After a few engagements we were aiming for the pelvic girdle. You hit the pelvic bone and it will drop them reliably.

I treated one bad guy with a hit to the abdomen and left upper leg. The wound to the abdomen had minimal bleeding and did not appear to have any internal injuries the exit wound was slightly larger than the entrance wound. The leg wound, same thing with the addition of slight bruising.

Another casualty I treated had a hit to his leg but it hit the femur. Totally different, the femur was shattered and leg was swollen to three times normal size. the exit wound was about the size of a soccer ball, with major blood loss.

The shorter barrel and collapsible stock are much better for CQB, I'll take a less effective hit in order to get some maneuverability.

It comes down to shot placement more than anything.