AK question

[CrudeGT]

Someone tried telling me the other day that the reason the Ak-47 is so deadly is because when the bullet leaves the barrel it is thrown into a vertical spin, as in end over end, and tears into a person that way. I laughed at him and said that it was complete bull, and he brushed it off.

but I got to thinking, I haven't fired an Ak and haven't read up on them much, so there is a possibility I just wouldn't know that.

Can anybody set me straight?


Thanx.

 

[Ben Shepherd]

What they are most likely refferring to is the bullets tendency to tumble after impacting the target. They do not tumble in flight.

 

[azrael]

HOPEFULLY he was referring to the Ak74 round...ahhh 5.45/39??? EHH something like that

Watched it on the history channel...what makes the round so deadly, is that when it gets in the human body it starts to "yaw", making a real mess of things..

 

[CrudeGT]

That's what I thought. I'm realizing more and more how much this kid BS's. I'm waiting for the navy SEAL stories to come out. I'll definitely post them if they do.

 

[chevrofreak]

The tip of the typical 7.62x39 FMJ round is hollow, which makes them tail heavy, causing the bullet to tumble when it enters a soft target.

 

[shermacman]

Ditto the above posters. This is a common urban myth usually repeated by Mall Cops. I have heard the same story of tumbling bullets out of the M-16's. A bullet tumbling in flight would be so inaccurate as to be unusable. Now, if you can get the bullet to spin stabilize normally in flight then tumble at contact with the target you have a real nasty meat blender. This feature is generally true of the ammo itself and not related at all to the actual gun it is fired from. The same tendency to tumble also makes the bullet more likely to stop on contact with body armor.

 

[TCD]

An AK 47 fires a pointy round through a barrel with rifling.


If the bullet starts to tumble in mid flight, there is something *seriously* wrong.



Tell your friend that he needs to go back to physics I

 

[benEzra]

Your friend is quite wrong. An AK bullet flies like any other bullet, point-first. And like practically ALL FMJ rifle bullets, it is heavier at the back than the front, meaning that when it hits major drag (like water, ballistic gelatin, a deer, someone trying to kill you, or whatever), it will try to turn (yaw) heavy-end forward. ALL FMJ's do this, but the lighter ones tend to yaw faster.

IIRC, the AK-47 bullet (7.62x39mm, nominally a 123-grain .30-caliber bullet) yaws after 8 inches or so. The AK-74 bullet (5.45x39) is lighter and has an air pocket at the front (making it even more base-heavy than normal), so it yaws in the first few inches. The 55-grain M193 round has a very thin jacket, so it tends to fragment as soon as it yaws sideways, if it is traveling faster than about 2700 fps.

None of the above are designed to yaw in flight, as this would make the darn thing less accurate than a musket shooting rocks.

 

[CrudeGT]

Cool, thanx for the info guys. He's one of those S&N people, ya know, when they start talking it's best to just Smile&Nod... So, we'll see what he thinks when I prove him wrong. Thanx guys.

 

[DMK]

The 7.62x39 has quite a reputation for overpenetration. Since the round is most commonly only 122-125ish grains, I assume that it doesn't even tumble reliably when striking soft targets.

Just remember, if any bullet tumbles end over end in flight, not only is it going to be uselessly inaccurate, it's going to leave keyholes in paper targets instead of round holes.

 

[benEzra]

CrudeGT,

I just noticed another blooper your friend made:

Someone tried telling me the other day that the reason the Ak-47 is so deadly

The AK-47 ISN'T "so deadly." A typical shotgun is far deadlier. See Dr. Martin Fackler on Stockton Shootings:

Madman shoots 35 in Stockton schoolyard [with an AK-style 7.62x39mm rifle]; 30 of those hit survive. . . .

To put the 17 January 1989 Stockton incident in context, it must be
compared with past shootings:

1. Only four of the eleven shot at the ESL Co. in Sunnyvale, CA, on 16
February 1988, survived. The weapon was a 12 gauge shotgun.

2. Only eleven of the thirty-two shot in the MacDonalds (24 July 1984, San
Ysidro, CA) survived. Of the three weapons used, the deadliest weapon by far was a pump-action 12 gauge shotgun.

Oh, here's a drawing of a 7.62x39mm FMJ track in ballistic gelatin. Notice how far it travels before it even begins to tumble (and that initial contact is point-first):

http://www.firearmstactical.com/images/Wound%20Profiles/AK-47%20762x39mm.jpg
Those measurements are centimeters; 30 cm is about 12 inches.

 

[Dave R]

My understanding is that the NEWER (since 1974) Russian 5.45X39 round is designed to tumble sooner/faster AFTER hitting the target. It is a long, narrow bullet with a hollow point. The hollow point is not to expand, like a hunting round, but to make the bullet unstable when it hits something reasonably solid. Like a human.

When in flight, the bullet HAS to stay stable and pointed, or accuracy and range would be lousy.

 

[Jim K]

Some of the British bullets for the .303 had an aluminum plug in the nose to make them front-end light and cause tumbling in the victim's body. The early AR-15's with the 1-7 rifling twist didn't fully stabilize the bullet and it also tumbled on hitting a target. In fact, this was a big selling point for Colt until the army caught on that the bullets would tumble on just about anything (leaves, twigs) and in cold weather didn't need to hit anything to tumble.

Jim

 

[TCD]

here'sa really easy way to prove the bullet doesnt tumble in air...



just go shoot some paper. Only thing you'll notice are normal bullet holes.

 

[BryanP]

The early AR-15's with the 1-7 rifling twist didn't fully stabilize the bullet and it also tumbled on hitting a target.

Minor note - I believe the early twist on the AR-15 / M16 was 1 in 14, which is why it didn't fully stabilize the bullet. Current twist is 1 in 7.

 

[ShaiVong]

Your right BrianP; Most new AR15's are 1:7 or 1:9... I don't remember if the A1's were 1:12 or 1:14 though.

http://www.ammo-oracle.com/body.htm#twists

Look at the 1:12 barrel firing M855 target on the right... If a bullet tumbled in flight you wouldnt be able to hit anything after like 50 yards.