223 FMJ designed to tumble (explained)

Rg176bnc

New member
I finally found out where this is coming from.
Was watching Top 10 Combat Rifles on the military channel and some British (expert) was spouting this. He said the bullet was designed to tumble when contacting flesh.

My personal thought is they us FMJ because bad guys hide behind cars,houses etc...

For enquiring minds the AK was #1 w/ M16 #2. BUT you can carry almost twice as much 223 at the same weight as 7.62 so not to worry were still better than the enemy
 
Originally Posted By: Rg176bncI finally found out where this is coming from.
Was watching Top 10 Combat Rifles on the military channel and some British (expert) was spouting this. He said the bullet was designed to tumble when contacting flesh.

My personal thought is they us FMJ because bad guys hide behind cars,houses etc...

For enquiring minds the AK was #1 w/ M16 #2. BUT you can carry almost twice as much 223 at the same weight as 7.62 so not to worry were still better than the enemy

the AK-47 fires a 7.62 X 39 round which is a very good round (smaller than the NATO 7.62 X 51). the reason behind why the US forces (as well as NATO) switched to the 5.56 round is for a couple of reasons.
1. they are lighter and you can fit more in a magazine
2. price. 5.56 cost less than 7.62x51 to manufacture

now the dowside to this is that a 5.56 round does not have as much kinetic energy dowrange as a 7.62 X 51, thus less stopping power. we still utilize a variety of weapons in the military that fire 7.62 X 51 rounds to include the M40A3 sniper rifle utilized by Marine Corps Sniper Teams, the M240G fully auto machine gun, and we are currently testing and working with developers to come up with a new M-4 variant that will fire 7.62X51 round (like an AR-10). plus a 7.62 X 51 is one of the most consistent rounds shot for shot ever designed. now if there is a bad guy hiding behind a car or a house they will more than likely employ the .50 cal BMG or even a .338 Lapua Magnum
 
The deal on the early M16s in the 60s,70s was the slow twist which barely stabilised the bullet.It was accurate enough,but when it hit anything,it would tumble,rather than bore through.
Even though the Geneva convention mandated a FMJ bullet(about as dumb as war itself)it was more distructive than any larger bullets in the battle.Now the ARs have twists as low as 1:7 and shoot bullets at 80gr,and win 1000 yrd matches.
 
Originally Posted By: Joe OThe deal on the early M16s in the 60s,70s was the slow twist which barely stabilised the bullet.It was accurate enough,but when it hit anything,it would tumble,rather than bore through.
Even though the Geneva convention mandated a FMJ bullet(about as dumb as war itself)it was more distructive than any larger bullets in the battle.Now the ARs have twists as low as 1:7 and shoot bullets at 80gr,and win 1000 yrd matches.

Huh?
a 1/12 twist stabilized a 55gr ball quite well. The military "ball" projectile was in fact designed to "upset" or "tumble" and the newer M855 with 62gr steel penetrator core will "yaw" just as predictably in soft targets as the old 55gr projectiles. This "upset" is a result of velocity, not R.O.T. The projectiles were designed this way to make allowance for the relatively under-powered .223 round. Battling with a .224 bullet is quite different terminally than a .308.

Ive heard this debate many times over the years but in every technical paper ive ever read on the subject, bullet upset was a design feature, not a mistaken result. The engineers knew what you give up with a .22 vs a .30cal. Overall, it was an ingenious design...(which btw, produces the same results as a .30 ball) All "ball" projectiles perform similarly in soft medium at similar velocities.
 
I heard that the reason the Military uses FMJ bullets is to wound people instead of kill them.If they wound someone it takes two to carry that person off of the battle field.So with that one bullet wound they are basically taking 3 people off of the battle field.I'm sure they do tumble but I did'nt know they were designed to do that.
I dont know if what I just said is true or not but I heard thats the reason the military uses FMJ's.
 
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Originally Posted By: OKRattlerI heard that the reason the Military uses FMJ bullets is to wound people instead of kill them.If they wound someone it takes two to carry that person off of the battle field.So with that one bullet wound they are basically taking 3 people off of the battle field.I'm sure they do tumble but I did'nt know they were designed to do that.
I dont know if what I just said is true or not but I heard thats the reason the military uses FMJ's.

this is something i have never heard of. what i have been taught my entire career is one shot, one kill. now i am not saying that this is true for all of the us military forces, but that is what we (USMC) are instructed from day one. the reason being is that a wounded man can still fire his weapon or detonate an explosive before he dies. a bullet from a wounded individual will ill you just as fast as a bullet from one whom is not wounded. when you are entering an area and you recieve fire or a threat, you need to neutralize that threat as quickly and efficiently as you can, thus shoot to kill, not shoot to maim. in fact it is against the geneva convention to intentionally maim your enemies. though the concept is not new (this was practiced by the viet cong)it is not one that is practiced by the us military. we use full metal jacket rounds because they kill, not because they maim. they enter the soft tissue of the body and cause a extreme amount of damage, thus ensuring that the likelyhood of a kill shot is improved.
 
Originally Posted By: Swift516I was always under the impression that using FMJ was Geneva Convention rules...?? Got me...

True that... The tumbling is inflict more damage..

I heard both in Nam, Geneva convention says FMJ. Some Army types said inflict casualties and wounded. Cartridge design was to tumble and inflict more damage.. Thats just what I heard in the Army..
 
ssgt walsh-I thought about that so I was'nt sure if that was exactly true or not.I just wish I could remember where I heard that.
I think I probably heard this in the same place but whoever told me about the FMJ's also told me that police officers use hollowpoint bullets because they are after one shot kills all the time.A hollowpoint is more destructive than an FMJ and they are less likely to go through or bounce and hit someone that does'nt deserve to get hit.I dont know if thats the reason for that or not either.But after I thought about it I really could'nt understand why it would be any different for the military.If a person is wounded that does'nt necessarily mean they aint gonna shoot back as you already mentioned.
I said earlier than a hollowpoint causes more damage than an FMJ and you said that FMJ's cause alot of damage and kill more humanely.I've also never shot a human being and hope I never do.All I've shot are critters and I know that FMJ's are'nt good for shootin coyotes.So I assumed it was the same way with a person because I just figured people were tougher than yotes.But then again.....like I said I've only shot yotes and stuff like that.I'll take your word for it but thats just somethin that crossed my mind.
 
I really doubt that the FMJ used in the military are designed to tumble when they hit flesh.

Can anyone offer an explanation as to how you would make a bullet tumble on contact without making it very inaccurate? I'm not talking about the odd bullet tumbling or doing something weird, we all know that once in a while a bullet will act unpredictably when it strikes a target. I'm talking about how one would make a bullet tumble predictably when it strikes a target, and at the same time be accurate.
 
The general purpose of using FMJs in battle is to incapacitate the enemy, rather than killing... By wounding, strategically you are requiring one or more personnel to care for the wounded and thereby effectively taking them out of the action, where a death will be dealt with at a later time...

Law enforcement, on the other hand, has the desire to use projectiles that in an urban environment are less likely to ricochet and damage innocent people or property...

Neither has a desire to kill... just to stop activity... In both cases, death is always an unfortunate possibility.

Any projectile, upon losing momentum, will potentially tumble...
 
Originally Posted By: OldTurtleThe general purpose of using FMJs in battle is to incapacitate the enemy, rather than killing... By wounding, strategically you are requiring one or more personnel to care for the wounded and thereby effectively taking them out of the action, where a death will be dealt with at a later time...



I disagree with you on this, someone on page one wrote a well worded post on this, I agree with it.

Quote:
Any projectile, upon losing momentum, will potentially tumble...

I know that, but that not anywhere close to "designed to tumble" that everyone likes to say, though can't offer an explanation for. There is a big difference between having a chance to tumble, and at normal ranges I would say it a small chance anyways, and being designed to do so.

I still can't fathom anyway in which you can design a bullet to tumble, and not upset accuracy to a huge degree.
 
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Please tell me you take anything you read on wikipedia or snopes as gospel?

Both sites have their own agenda and truth is not high on their list.

Jack
 
I was hoping Jack had this straightened out .......

...... after reading this whole thread, my head is going to "tumble"!!!

I would only suggest this much:

The FMJ's are an agreed upon requirement of the Geneva Convention.

Police use HP's for a reduction in overpenetration.


**********************************

Three 44s
 
And now our military can and does use the 30cal 175 gr Sie HPBT.It mneets the criteria of the Geneva convention for not only terrorists but national armies.
I never believed that the first .223s were "Designed to tumble",and I never encountered that happening ,on paper.However,they were conditionally unstable,causing them to tumble ,if you will,after hitting solid mass.For instance,I have a .243 Sako bought in 1960,that shot 75 gr Sie HPs very well with a untuned gun.The hunting bullet available (Germany) was a 105gr Speer PSP.I couldn't get groups below 1.75",because the twist was too slow.(advertized as 1:10,but neasured on numerous occasions,closer to 1:11.I drove them pretty hot.Hit a Reh Buck (50lbs), behind the shoulder,standing broadside,at 45 yds.The bullet did not exit,but was in pieces ,under the skin, on the far side.Of course the velocity causes more of the hydrolic shock than the bullet stability.These bullets were conditionally unstable in my barrel
 
I can tell you from 23 years experience as an infantry officer, the m16 bullet was not designed to tumble. if it does not hit bone, it is like a needle going thru flesh. if it hits bone, and the tip of the bullet is deformed, it will tumble. I have seen a bad guy take a 20 round mag of 5.56 stuff thru the stomach area and never know he was hit.
I have seen a bad guy get hit from 15 yds with 3 rounds thru the head .224 bullet hole in and out.
trust me, if we designed a bullet to tumble, the bad guys would be all over the UN about how terrible/cruel we are.
 
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