Posted on 02/02/2007 12:23:59 PM PST by John Jorsett
Troops from the U.S. Army and Marine Corps are still complaining about the "inadequate stopping power" of the 5.56mm round used in the M-16 family of assault rifles. Last year, the army did a study of current 5.56mm M855 round, in response to complaints. Troops reported many reports where enemy fighters were hit with one or more M855 rounds and kept coming. The study confirmed that this happened, and discovered why. If the M855 bullet hits slender people at the right angle, and does not hit a bone, it goes right through. That will do some soft tissue damage, but nothing immediately incapacitating. The study examined other military and commercial 5.56mm rounds and found that none of them did the job any better. The study concluded that, if troops aimed higher, and fired two shots, they would have a better chance of dropping people right away. The report recommended more weapons training for the troops, so they will be better able to put two 5.56mm bullets where they will do enough damage to stop oncoming enemy troops. Marines got the same advice from their commanders. But infantrymen in the army and marines both continue to insist that the problem is not with their marksmanship, but with the 5.56mm bullet. Marines say they have used captured AK-47 rifles in combat, and found that the lower velocity, and larger, 7.62mm bullets fired by these weapons were more effective in taking down enemy troops.
The army study did not address complaints about long range shots (over 100 meters), or the need for ammo that is better a blasting through doors and walls. The army had been considering a switch of a larger (6.8mm) round, and the Special Forces has been testing such a round in the field. But a switch is apparently off the table at the moment. The army report was not well received by the troops, and there is still much grumbling in the ranks over the issue.
I knew that...
(Conversely, the sights are calibrated for bullet's natural travel and the rifle is quite accurate at distance.)
This is an old debate that goes as far back to Vietnam, Robert McNamara and the bean counters. IMHO I would take a 7.62 round over 5.56 any day.
Nothing like a double tap to clear a room.
No argument on the M-14. The BAR was a great weapon, but it was too heavy to be a standard infantry rifle. It was used in the Squad Automatic Weapon role, and that's where it was best at.
The problem with our military's choice of round selection is that politics, DOD careerist aspirations and people without combat experience are what rule the choice of weapons, ammunition, etc.
People who pay attention to ballistics, both exterior (ie, in-flight) and wound ballistics have known for a long, long time (since the late 1920's) that a bullet diameter somewhere between 6.5 to 7mm (.264 to .284") has optimum exterior ballistics and that in this range, a moderate weight bullet (say, around 120 to 140 grains) has excellent wound ballistics in a solid, non-expanding round.
The problem is this: When the US entered WWI, we were well behind the curve in rifle technology. The 1903 Springfield was basically a rip-off of the Mauser action. We chose a .30 bullet diameter based on experience up to that time. Out of the pre-WWI and WWI experience, we come away with the 1903 Springfield rifle, an excellent bolt gun, and what we all know today as the ".30-06" round.
At this point in military history, the emphasis was on "aimed fire" and the machine gun was a new invention and not well co-ordinated with military doctrine at that time.
Along comes the 20's and early 30's and some people start thinking about semi-automatic rifles and volume of fire from individual infantrymen. The Army "Gravel Bellies" don't like the idea of semi-automatic weapons -- "wastes ammunition and nothing more!" they proclaim. The consideration is made that the .30-06 is a tad heavy to carry, a tad heavy on the recoil, and we could get more bang for our bucks by using some real science on the issue of bullet selection.
So the Dep't of the Army forms what is known in history as "The Goat Board." They prop up quite a number of goats and goat carcasses to test wound ballistics and lo, they come up with the result of bullets in the .270 to .276 region seem to maximize everything we're looking for in a battle weapon's ammunition.
Well, the aimed fire bureaucrats in the Armory system aren't going to hear of a "wimpy" sub-.30 round. Just won't hear of it. There were still some fossils in the Army who thought that the .45-70 round was entirely sufficient, if only the infantry would be trained to use very judicious, carefully aimed fire. Mind you, the .45-70 killed people deader than an anvil with very few bullets, but loaded to modern ballistic capabilities with smokeless powder instead of 70 grains of black powder, it kicks like a pissed-off mule.
No one was buying the idea of a sub-.30 bullet, so the bureaucrats point out that goat flesh isn't a good approximation of human flesh for testing would ballistics, so they force a repetition of the wound ballistics tests, only this time with pigs, because pig flesh is a better approximation in density and depth to humans.
And so, the "Pig Board" was formed. They repeat the tests and arrive at the same result. About a .270 to .276 bullet seems to optimize everything we're seeking.
The gravel bellies are now worried. They're running out of excuses to keep the .30-06. So they fiddle, twiddle, piddle and delay and debate the issue some more.
Now it is the late 30's. People who don't have their head up their backside are looking across both oceans and seeing the winds of war start to pick up. The sane people of the day can see this coming, and one of these sane people was Douglas MacArthur, who, at that time, was in charge of the decision whether we're going to chamber the newest battle weapons (eg, the M-1 Garand, etc) in this new .276 caliber or in the .30-06.
MacArthur looked at the huge stockpiles of .30-06 ammo we had in stores all over the country. And then he looked at the fools in Congress, as well as in the Dep't of the Army. And MacArthur made the decision that perhaps saved our asses early in WWII: he said that logistics trump all the science, and it was better to have a good, solid, if sub-optimal round than no ammo at all.
The most valuable M-1 Garands for collectors today aren't the Garands that got issued. They're the very few prototype Garands that were made in .276 Pederson round (7x43 mm), a round much closer in power to what was necessary for a assault weapon with ranges out to 500 meters, instead of out to 800 meters.
Fast-forward to prior to Vietnam: the Army wanted an assault rifle. The "gravel-bellies" were back in the saddle, and all the science from the Goat Board and Pig Board was swept under the carpet. The Armory bureaucrats wanted a "full power .30" round in a fully automatic rifle, and told Mr. Garand to develop this.
John Garand told them it couldn't be done. Nonetheless, Garand labored long and hard and came up with the M-14, which as other people here have said, is tough to control on full rock-n-roll settings. The Dap't of the Army grudgingly allowed a reduction in power from .30-06 to .308, mostly to gain reliability in action cycling.
We get into Vietnam with the M-14. A wonderful, tough rifle for marksmen, but because it couldn't be controlled easily in full auto, and because it had no burst-fire mode, it was a bear to control. It was much harder still to give a M-14 to a ARVN and tell him to do anything useful with it. The rifle is simply too large, too heavy and kicks too hard for someone of slight frame and small dimensions.
Along comes Eugene Stoner and the AR-15/M-16. The DOD bureaucracy *hates* this, but gets it crammed down their throats by McNamara, along with the 5.56 round, which is simply too small and too light for longer shots. If someone here would like me to expound on ballistics, I can, but for now, I'll keep it short and say that small, varmint-sized rounds can be highly frangible, even in solid-bullet configurations, but they need high velocities upon impact to break apart. The problem here is twofold:
1. It takes a longer rifle barrel than the AR-15/M-15/M4 (especially longer than the M-4) to fully burn all the powder in the cartridge and maximize the velocity of the bullet. Most varmint rifles have at least a 24" barrel. The M-16 has a 20" barrel. The M-14 has something like a 14" barrel. The shorter the barrel under 24 inches, the more powder that leaves the muzzle as unburned powder and the brighter the muzzle flash.
2. The spectrum of bullets (diameter x length x weight) has a few "sweet spots" where everything comes together. Us gun nuts have known this for years and years. .223 is not one of those sweet spots. .30/.308 isn't either. Some of the smaller-caliber sweet spots are:
6.5mm (.264) -- very high ballistic coefficient and sectional density for the weight. Best bullet in this caliber would be a 160grain bullet. Terrific sectional density, and terrific ballistic coefficient. This bullet keeps its kinetic energy for a long, long ways downrange. There are plenty of long-range shooters using wildcat 6.5mm rounds at 1000 yards very successfully.
7.. (.284) -- almost as good as the 6.5 at the same weight, but really good at heavier weights.
.338 -- at the 300grain to 325 grain levels, the .338 is an excellent long-range round. But it is so heavy that you need something like a .338 Lapua to launch this, and now we're in the realm of dedicated sniper rifles.
.404 -- the .404 CheyTac is a new sniper system under development.
And then we find wonderful ballistics in the .50BMG, which is obviously too heavy for individual infantry.
So, out of all of this, the 6.5mm is really the ideal situation for an infantry rifle, just as discovered before computers by the Goat and Pig boards. The 5.56 (.224 diameter) bullets have horrible BC's, and bleed off their energy very, very quickly, and penetration is a function of velocity. Couple this horrible BC rating with the trend towards shorter and shorter barrels, which rob the bullet of velocity right out of the muzzle, and you get what we have here today: a worst of all worlds situation: the bullet is too light to have knockdown on unarmored targets, it has no hope of penetrating body armor at any distance, it doesn't have any long range killing power on something bigger than a poodle and it sucks as a CQB weapon, where what would be ideal is a fat, slow bullet (like, oh, a .45 ACP out of a sub-gun, or a short-barrel shotgun).
Sadly, the DOD today seems intent on turning the M-16 into a jack of all trades and a master of absolutely nothing. Further trouble is, the DOD now has a lot invested in the 5.56 and they're slow to do anything.
A 6.5mm bullet, perhaps in 120 grains, with a moderate cartridge behind it (say, something like a .308 necked down to 6.5mm -- aka the ".260 Remington" would have much more knockdown power, much more range, yet still be very mild in recoil and fully managed in full-auto by anyone in the infantry. It wouldn't be ideal in CQB. We still need to get the DOD to realize what we realized in WWII: there are lots of situations in urban combat where our guys need something that puts down a volume of fire that's very lethal at close ranges, much like what we had in WWII with the Tommy Gun and the M-3 "Grease Gun."
As for piecing body armor: that's tough to do. The projects extant to do this typically use very small diameter bullets (say, 4.5mm or .177 cal) and very high sectional density (they look very long and carry some higher weight) with a very sharp, non-deforming tip. They're not going to kill someone at long range, and the wound ballistics must be about that of a knitting needle. Yes, the guy is hurt, but the wound channel will be very narrow and not cause immediate death unless the projectile hits a very critical area.
So if you're wondering why our guys are saddled with this varmint round suitable for dispatching nothing larger than a coyote, here's your answer: Literally 100 years of malfeasance on the part of the Army/DOD bureaucracy.
Meant to say (FR needs an edit capability):
M-4 (M-four) has a 14" barrel. The M-14 barrel is entirely sufficient for what it does.
And, for the record, as a semi-auto rifle, the M-14 is a wonderful weapon. Just outstanding. What it isn't is an assault rifle. What it also isn't is a weapon for close, tight situations. It is a full-sized rifle for full-sized men who can handle full-power rifles, just like the Garand was.
One of the best gun writers and researchers was one Col. Townsend Whelen, for whom the .35 Whelen round is named today.
The late Col. Whelen was a very astute gun researcher and writer before today's idiots took over the pages of hunting and shooting magazines. Col. Whelen walked his talk and was a most interesting man, having a career and hobby of firearms from the .45-70 Trap Door clear through to the Garand and M-14.
One of his most fascinating articles was titled "Just a Little Bit More" and extolled the virtues of what you're saying: A 7mm-06, or .280/.284 bullet on a .30-06 case. It kicked a bit less, it went a bit further, it hit a bit harder. Col. Whelen's opinion was that if you had a perfectly good .30-06 or .270 Winchester hunting rifle, you should not bestir yourself to get rid of it in favor of a .280, but that if you were seeking one rifle with which you could hunt anything in the lower 48 states, a .280 deserved some very close examination.
After years of being abused by a .338 Winchester Mag and a couple of hunts with lighter .250 or similar rounds where a wounded animal walked off, I'm now in complete agreement with Col. Whelen: Something like a 7mm-06 would be absolutely ideal. The selection of bullets is outstanding, the ballistics are outstanding and the performance of this cartridge with modern powders makes the 7mm RemMag basically obsolete.
And, FWIW, I was recently flipping through the pages of one of these glossy, idiotic hunting magazines where they did an "efficiency" test of various hunting rounds, based on how much kinetic energy did one get for how much powder and recoil?
Guess what round came out on top?
The .35 Whelen, which is nothing more than a .30-06 necked up to take a .35 bullet.
Coincidence? I rather think not. There were no accidents coming out of Col. Townsend Whelen on the subject matter of ballistics. It is a shame that the current DOD people seem unwilling to go back and read what was written by one of the most fertile minds on ballistics the US military ever had.
"The M-14 I carried was modified for full auto. I never had a problem as long as I stayed with short bursts."
Short bursts are definitely the way to go, wnen I shot it, I wanted to experience the M14 to the fullest, first with a short 3 shot burst, then finishing off the rest of the mag with one squeeze. The 3 chevy vans down range, already looked like swiss cheese, so who knows what I hit, but it sure was cool !
You are correct, sir.
I was mis-remembering.
The 62gr round is slightly longer, which is why the 1/7 twist rate was derived for the M-16A2. The bullet is slightly longer, but deeper set into the case so that OAL will fit in the standard magazines.
The "penetrator" has marginal effects, which is why the M855 round isn't considered armor piercing by either the military or even US code.
Let's see:
1. Much less ergonomic. That's why many of the M14s that are being refielded are seeing completely new stocks.
2. Less accurate. YES. The piston design of the M14 puts pressure on the barrel, which significantly effects shot groups. By comparison, the M16 has just a little gas tube that inflicts minimal deflection on the barrel during recoil. The M16 is overtaking the M14 at ranges out to 800m with the right ammo. Even them, combat engagements with rifles past 300m is rare and under 100m is the norm.
3. Less adapatable. Even with new stocks, the M14 is a pain in the ass to mount a decent scope, let along lights, lasers, etc. I can bolt on a $200 tube to the M4 but I have to completely re-stock the M114 at a cost of nearly $1000. If we wanted a 7.62mm rifle, we should have adopted the FN FAL.
4. Even if you go with a "bush" model M14, the 14.5" barrel of the M4 carbine is much easier to use in a MOUT envrionment. It's lighter weight means it's easier to maneuver quickly.
5. Controllable under automatic fire. No contest. The M14s ability to use this feature is minimal. Meanwhile, I can keep the M4 controlled on a 25M target through the entire magazine.
The M14 was one of the shortest-lived issue weapons in US military history, while the M16 platform remains the longest.
this is why when I was going to buy a battle rifle, I bought an AK47
I'd put up an M14 against an early M16 any day. I remember the early M16 with the wimpy barrel was very inaccurate if fired using the sling as we were taught in USMC rifle training. The tension would bend the freaking barrel enough to make it impossible to find a zero. The Marines did manage to get the M16A2 barrel strengthened as well as give it decent sights. I think I noticed all the target M16 derivatives have floating barrels now as well.
I liked my HBAR very much, it was a very accurate rifle, regardless of the stopping power. My Mini-14 on the other hand was useless beyong 50yds, but was a cool little rifle.
7.62x51 (.308 Nato) is the way to go.
Excellent stopping power, excellent range.
Use the SOCOM 14 for house to house sweeps.
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