Wouldn't tumbling an FMJ get you back into smashing territory (like hollow points) and get you back into more mortality?

Yes, along with more serious wounds. Everybody wins!

Wouldn't tumbling an FMJ get you back into smashing territory (like hollow points) and get you back into more mortality?

Not exactly. A tumbling fmj assault rifle round doesn't smash. It carves a very large and very nasty path through the body.

It carves a very large and very nasty path through the body.

How does that not up the mortality rate, though? It's precisely why hollow points kill better, no?

How does that not up the mortality rate, though? It's precisely why hollow points kill better, no?

Sorry. The "not exactly" was referring to the "smashing." You are correct in that it's back into the higher mortality rate.

Actually, I think DX, Nutty and I are all arguing from more or less the same position, we're just quibling about the design intent, just not very successfully.

I was using the word smash to convey not drilling, but the whole large nasty non-precise damage inflicted thing. Sounds like everyone is almost in agreement.

Secret message to beathen, although, really, anyone can look if they want to:

Don't worry about it. Reading will just slow down the typing. I should have both 3 and 4 for you this weekend. Sorry I'm so slow!

Yeah, I think we're all in agreement and just not seeing it very well. I know I have perhaps not expressed myself as well as I'd have liked.

I originally entered this discussion to quibble with Nutty's characterization that switching from a design that caused a small, tidy wound to one that causes a large, messy wound was going from more to less lethal, but I also suspect I may have misunderstood the point she was trying to make.

Thanks for all your help libkitty!

Aack! There is a difference between the spin of the bullet imparted by rifling and the tumble of a bullet within the target.

From post #3677, Nutty:

this is the same reason why bullets are designed to spin sloppily

and post #3680, Nutty:

Most modern guns pon't back the bullet tightly into the barrel, so when it comes out its spin is as messy as a kindergartener throwing a football.

and post #3684, DXMachina:

The M-16, for one. The bullets tumble in the same manner a knife tumbles when you throw one at a target

and post #3698, Sean K:

Back when military rifles were rifled, very few soldiers could shoot well enough to kill with one shot. The rifling was removed to make them more lethal, not less.

No. Military rifles are still rifled. The bullets come out spinning, not tumbling. High-velocity low-calibre bullets like those from an M-16 tumble and often fragment after penetrating the body of the target, but they don't tumble on the way to the target. That would make for accuracy worse than a BB-gun.

IIRC the rifling on the current models of the M-16 is 1 rev. in 7 inches and some earlier models had 1-in-9 and 1-in-12 rifling.

From an ICRC article [link] :

"Wounds from projectiles that strike the body at more than about 800 metres per second differ both in degree and in kind from wounds caused by lower-velocity projectiles. Because of the tendency of high-velocity projectiles to tumble and become deformed in the body, and to set up especially intense hydrodynamic shock-waves, the wounds which they cause may resemble those of dumdum bullets".[10]

and

According to Sellier and Kneubuehl, a bullet which is fully enclosed in a metal jacket, as are virtually all military rifle bullets today, will start to turn around a lateral axis at some distance after entering the body. Once it starts to turn, the rate of turning increases rapidly; the angle of incidence reaches 90 degrees and the bullet continues turning until it is travelling nearly tail first. After that, it can partly turn several more times before entering the last phase, when it will again be travelling tail first. Depending on its construction, a full-metal-jacketed bullet can deform or break up because of the stresses placed on it during turning, but deformation or break-up of a full-metal-jacketed bullet is a by-product of turning and not an independent process, although, once it happens, the deformation or break-up adds to the wounding effect because of the increase in the surface area of bullet material pressing against the tissues.[20]

The turning, or "tumbling", of a bullet is thus the critical mechanism resulting in severe injury, and the likelihood of causing a severe wound will depend on how far a bullet penetrates the body before turning. An ammunition designer who is intent on inflicting the greatest possible damage will want to have the bullet turn as soon as possible, thus achieving the same effect (rapid transfer of most or all of the bullet's kinetic energy) as with the outlawed dumdum bullet.

So, what makes a bullet tumble?

According to Sellier and Kneubuehl, the tendency of a bullet to tumble early on entering the body is dependent on the angle of incidence on impact, the shape of the bullet nose, and the gyroscopic stability of the bullet.[24] Gyroscopic stability, in turn, is dependent on such factors as the rate of spin, the moments of inertia, and the geometry of the bullet. In general, the greater the gyroscopic stability of a bullet (for example, because of a higher spin rate), the further it will go in the body before starting to tumble; and the shorter a bullet is in relation to its diameter, the less likely it is to tumble.

t stuffs arguments back up heinie from whence they came

(And I thought M16s were still rifiled, but didn't say anything, because it was making my brain hurt trying to reconcile it with the rest of my arguments)