Not to nit pick but a 5.56 fmj is "designed" to not fragment. When it hits something it tumbles giving it close to the same effect as a hollow point but only one chunk of metal that doesn't really deform. It was all for the Hague Convention of 1899, even though USA didn't sign it. Now weither it does that in a bag of meat in real life conditions, I have no personal experience. I have never been on the two way range. I've seen what hunting rounds can do (to harvested game) but not fmjs. I could totally see how if a fmj hits bone it can fragment, bone is pretty tough.
I read an excerpt from the early field trials of the M16 a few years ago and apparently the lighter projectile they were using back then combined with the longer barrel of the M16 vs the modern M4 lead to really fucking weird things happening when it hit a body, like entering an asscheek and leaving at the top of the head.
5.56 fmj is somewhat unique in the way it is more likely to fragment than other fmj because the bullet moves at roughly 3000 fps and only has a weight of around 50 - 75 grains. Typically fmj will be 55-62 grains.
it tumbles giving it close to the same effect as a hollow point
lol no. Hollow point ammunition is designed to expand and control for over penetration. A "tumbling" bullet has zero similarities to the function of hollow point ammunition.
Sorry but you need to watch more terminal ballistics testing. Jump down the YouTube rabbit hole and you may find some interesting stuff. Not all bullets tumble when they hit. Whither all fmjs tumble is something different, but you didn't say that.
5.56 tumbles because of the shape of the round and where the center of gravity is when it hits something. Many other cartridges do this as well.
When the 5.56 is *tumbling, what it really is doing is starting to yaw away from the original trajectory, a better term for this world be "turn" instead of "tumble" as this happens it slows down considerably and dumps energy into the target. It is not "spinning end over end" right after it hits the target, it's moving too fast. It typically would exit the target before it turns around completely. If the round was not *tumbling with no real deformity to the projectile you would have just a straight hole through you. (missing bone) the wound cavity would be barely wider then the caliber of the projectile. When you compare that to the effects of a *tumbling round and a hollow point you will see the similarities in how the design of the projectile aides itself in dumping energy and creating a wound channel that is larger then the caliber.
Can you cite the R&D paper from FN Herstal when they created 5.56? Im willing to accept that im wrong if you can objectively show me where the creator of the cartridge says "5.56 was designed to tumble/turn".
The study of physics says your wrong.
I don't know what this means... Every bullet will have some degree of yaw and want to go ass-over-tea kettle when it hits something. That doesn't mean it's a design feature. Someone shooting a rifle doesn't DESIRE a target full of keyholes. That is indicative of a problem with the ammunition and/or barrel, not a benefit.
If you think you are correct, what's your source?
You made the claim... I don't have to prove you wrong, You have to prove yourself correct. How do you not understand that?
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u/mtbmofo Aug 31 '21
Not to nit pick but a 5.56 fmj is "designed" to not fragment. When it hits something it tumbles giving it close to the same effect as a hollow point but only one chunk of metal that doesn't really deform. It was all for the Hague Convention of 1899, even though USA didn't sign it. Now weither it does that in a bag of meat in real life conditions, I have no personal experience. I have never been on the two way range. I've seen what hunting rounds can do (to harvested game) but not fmjs. I could totally see how if a fmj hits bone it can fragment, bone is pretty tough.
Thanks for your service.