Ah! rumors about the early M16's "unstable bullet"

C

CrazyLarry

New member
Venturing throught gun shops lately, I came across a Vietnam-era replica AR-15. The owner then began to spout off how that is truly what the M16 is all about, no charging handle/brass deflector so it is truly light, and a barrel twist that makes 55gr bullets lethal. This particular AR was chrome lined, but otherwise it was just like a Vietnam era rifle (sans full auto).

Then I come on here and read somwhere in here.....I believe:
http://www.ammo-oracle.com/body.htm
That this is all gunshop BS and that the bullet design is what makes a bullet unstable, not the twist rate. Rumor dispelled becuase we are scientists etc. etc.

Well, today at work I asked one with experience. A guy I work with, Tom, served in Vietnam from 65-66. When I questioned him about this ever holding true, he said that indeed, the bullets were unstable. he told me of hitting guys running in the upper shoulder (entry) and then seeing the exit wound come out of their lower abdominal, blowing out intestines. Tom claimed the rifles weren't bad, just kept it clean and never had any real problems with it. However, he did say the ammunition was crappy, that the brass was very thin and "soft." Due to this he claimed that when they were resupplied they would often dump live ammo (the old stuff they had carried)in the field to get rid of it. This they did by burying in fox holes as they left, but Tom said when they came back to these old sites the fox holes would be dug up. anyways, supposedly if they got the slightest rust/corrosion the ammo would really jam.

Also stated that while guys bitched about getting the M14s back, he loved carrying 800-1000 rounds of ammo on himself. And BTW, he was airborne and truly saw a lot of combat, also getting wounded i.e. this is a pretty reliable source.

Just thought it was interesting coming from first hand from him, great guy to listen to.
 
... the bullet design is what makes a bullet unstable, not the twist rate.
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I don't think it's that simple. The twist rate determines a range of bullet weights for best accuracy. Given a bullet weight within the range determined by the twist rate, I suppose a poorly designed bullet could cause poor accuracy performance, but that would have to be a really crappy design. Jamming? I can't make that connection. As I understand the early AR story, there was defintely a mismatch between the bullet weight and the twist rate of the rifling.

Now, corroded casings! THAT could definitely cause some cycling problems.

More knowledge will undoubtedly stop by this thread and straighten me out. :)
 
No spitzer bullet is stable in dense media like water... or meat.
The question is, does it fragment or "tumble" in a way that makes it more damaging? Viet Nam era M193 ammunition is said to break up at the cannelure; current M855 at the seam between lead and steel cores; IF the velocity is still high enough/range short enough. Farther out, you depend on the bullet yawing or "tumbling" to enlarge the wound.

The British found the very stable .303 FMJ roundnose less effective on Afghans et cetera than lead .577-.450s. So they tinkered around with the original cut-nose Dum-Dum and several successive marks of expanding bullets to the point that they had to assure the early meetings at the Hague that they would maintain inventories of FMJs for declared wars against "civilized" nations, and keep the hollowpoints set aside for shooting at savages.

Their traditional Continental adversaries and allies begged to differ and the British gave up on that plan.

This all became academic when everybody started going to spitzer bullets based on the French Balle D and found that the pointed bullets would turn over on impact and make a wound nasty enough for any purpose. The British enhanced the effect with a light insert in the jacket nose of the Mk VII bullet.
 
The original 1 in 14 twist was more lethal than the later 1 in 12 twist which is more lerhal than the current 1 in 9 inch twist.
 
he told me of hitting guys running in the upper shoulder (entry) and then seeing the exit wound come out of their lower abdominal, blowing out intestines.
...
BTW, he was airborne and truly saw a lot of combat, also getting wounded i.e. this is a pretty reliable source.
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So Tom is there in 'nam. There is an enemy running along and 1 and only 1 soldier fires a single shot at the running man and he is hit with one round going in the upper shoulder and his intestines are blown out his lower abdomen with M193 ammo? It has to be only one guy firing as that would be the only way to know that the shoulder round is the round bursting out the intestines

They don't make ammo like that anymore.

I spoke with a guy who served in the late 60s. After I purchased my first AR15, he told me how the ammo was designed to "crawl around inside the body." If you shot a guy in the arm and it hit bone, it would crawl up the arm, following the bone, thereby doing more damage than had it just passed through.

I honestly don't think many soldiers ever really knew the design history of the firearm or ammo while in 'nam. As with other wars, I don't doubt they were told many things about the superiority of the firepower and such, but a lot of it wasn't completely true.
 
I vaguely remember on my last "all expense paid vacation" to the Far East (1972) that I ran across the formula for twist and stabilization in a Gun Digest Treasury (I no longer have it - it bit the dust in one of my divorces...). I ran the numbers for a 55gr pill at 3200 fps in a 1 in 12 or 1 in 14 twist (I don't remember which) and I think the result was that it would stabilize a bullet 1.4 inches long... Unfortunately there was no formula to tell when the bullet was "over stabilized" but my hunch was that at that rate of twist, it was.

The next point is basic Physics 101 - conservation of energy. By the time the bullet (and fragments) all come to rest, all the energy must have been used to do "work" - and that includes rotational energy from a high rate of twist. This "work" usually resulted in damage to the target.

A good rule of thumb for stabilization is Greenhills Formula (I don't think that was the one I used in 1972) - If you Google it on the web you can probably find it and some good commentary.
 
The original M16 rifles of the early 1960's weren't nearly as accurate as the A1 or A2. At close range, though, the little rounds did tear things up. Much like the early reports of the Soviet 5.54x39 rounds. There were some documented close-range shootings that revealed the bullet taking a strange path. These were, unfortunately, usually from draftees attempting to leave the combat zone.

The rifles themselves were incredibly sensitive to powder fouling, the presence of corrosion in the unplated chambers, rough chambers straight from the factory, and the flimsy magazines issued at the time. The use of ball powder also resulted in a much higher than design firing rate, and buffer failures.

The flash-supressors, of the open-end type, were also difficult to manuver through the jungle without fouling on the undergrowth. We also found that the things would wick moisture up the barrel via capillary action during movement through wet foilage.

The rifles would also fail to drain quickly after immersion.

As to cleanliness. The initial instruction stressed how clean the weapons operated, and that the necessity for cleaning had been greatly reduced. They issued one cleaning rod for every three rifles!

I went through three M16 rifles in November of 1967. All but one failed due to bolt-over jams. The one that didn't was traded immediately prior to firing to an ARVN Ranger for his M2 Carbine, a bunch of 30 round mags, and most of a case of ammo.

In the end, I went back to my original M14 rifle.:) :)
 
So your Para buddy carried 1K rounds on him?
And somehow the ammo they carried was no good once they got "new" ammo which may have been older than what they had?

Just because they were there doesn't mean they know what they're talking about. As an example, we have a Ranger who is adamant that the AK47 is an open bolt gun.
 
+ 1 Jim.

I have fired a lot - and I mean a lot- of mark 7 .303 ball at various critters over the years. My dad used to go mental if I ground the nose off to make them into crude hollowpoints due to the risk of jacket seperation in the barrel, so I was using the mark 7 load as issued. If it hit a bone it really did start to open up, but if it passed through without h itting a bone it was useless.
 
In '72 we were told the M-16 bullets tumbled on impact in USAF SP school.
In '94, I was doing a project with a 16-inch .223 and a 16-inch 9mm AR, part of which involved firing into my penetration box with several 8-inch squares of one-inch pine lined up about a half-inch between each one.
.223 55-grain FMJ tumbled as it passed through the boards and came to rest base forward. 9mm FMJ did not tumble, penetrated farther, and came to rest nose forward. Interesting enough, the 9mm AR was slightly more accurate at 100 yards. Both ARs were Colt Lightweights.
I have not used the .223 on people (been lucky), and FMJ results do not necessarily translate to HP performance. There are a number of factors involved- bullet weight, rifling twist, velocity, and bullet construction are all included.
Denis
 
yeah I would probably opt for ammo straight off a helicopter and in the case still, compared to stuff i had been humping around in a jungle with for days on end.

Make sense??:eek:
 
Hitting the target is more important

I believe the whole thing was a major mistake (tumbling bullets etc.).
They finally figuered it out, at the cost of many lives (expendable comes to mind).

The Department of War must have figured that one out also. Very slowly though. (Absolute screw up, the whole thing. A majorl scar on the US and the servicemen who had to go through it and give their life for the mistake's made).

Robert McNamara and his war was a Cluster fxxx from the get go. IMHO. Then they put him in charge of the World bank. Go figure:eek:

HQ
 
Robert McNamara and his war was a Cluster fxxx from the get go. IMHO. Then they put him in charge of the World bank. Go figure
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That's the Kofi Annan school of management (i.e. see Bosnia, Rwanda, and then Kofi's promotion to Sec Generalship . . .). In jobs where you can manage to be held unaccountable for anything you do, no matter how utterly disastrous, how can one help but move on up?
 
A tumbling bullet, as it penetrates live tissue, is actually desirable in a light FMJ bullet in that caliber and in that role. It does much more damage in passing than an FMJ that doesn't. Think about it. Remember, this tumbling starts after initial penetration. The entrance hole is a perfect circle, like any other type of bullet would be. The tumbling was not a major flaw of the M16 system.
Denis
 
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