.44 Magnum the same as .308?

[BigDogatPlay]

For what it's worth Chuck Taylor wrote an article twenty or more years ago for SWAT magazine where he suited up with what was then state of the art hard body armor (kevlar plus ceramics) and allowed himself to be shot with a variety of calibers at a distance on one meter. The calibers included .44 Mag fired from a 6 inch (IIRC) 29 and .308 fired from a Galil.

In the article Taylor expressed surprise that he felt more energy against his body through the armor from the pistol round than from the much higher powered rifle round.

Completely anecdotal, but there it is.

[locosway]

I've actually seen the video.

[elSquid]

What matters is the diameter of the hole and how deep it is

I'd agree. It just seems to come down to the characteristics of the permanent crush cavity.

-- Michael

[locosway]

If we all agree on that, then my model should be somewhat accurate in showing differences between rounds.

[BlackDrop50]

Hmm..well personally I would be more afraid of a 308 but only because it's traveling so fast.


If it matters at all, I know a guy shot in the face with a .44 mag at 5-10 feet. He survived but with major injuries and is disabled for life. He raised his hand and that probably slowed the bullet a little.

[elSquid]

If we all agree on that, then my model should be somewhat accurate in showing differences between rounds.

Define "somewhat" accurate?

Until your model can predict the cavity from a 7.62 FMJ



and a .308 soft point



I'm not sure how useful it will be.

But I think we've gone over this already, so I'll just shut my yap from here on out.

-- Michael

[locosway]

hehe, yeah, I don't want to predict a cavity. I was just looking for a number that was tangible to compare to other rounds.

[ivanimal]

I like your theory and think its good science for quick comparison. Like the Horse Power example.

There are too many variables to please all. This is just good common sense science to rate different round of different types. Thanks for the footwork and edjumacation.

[locosway]

I'd agree. It just seems to come down to the characteristics of the permanent crush cavity.

-- Michael

You know, I bet with enough real world testing you could accurately come up with a mathematical formula that explains cavity creation.

I really suck at math, so I wouldn't be the one to make such a thing, but it's possible. Since it hasn't been done yet, I guess people don't see it as something necessary.

[FullMetalJacket]

The "linebacker" analogy of "energy dump" is not apt because it neglects that (1) the time involved in the collision of a bullet with a body is much, much shorter; and (2) the interacting areas are much, much smaller.

We all know from high school physics that energy is the ability to do work. No energy, no work. Displacing body tissue from its equilibrium position is work. So do two bullets with the same energy do the same damage even if their mass and velocity values are different?

Probably not. A bigger diameter bullet impacting a body will act on a larger cross section of tissue than a smaller diameter bullet will. This should serve to "drag" the bullet's speed down more rapidly and keep it from penetrating deeper. This somewhat follows our common sense that higher speed rifle bullets penetrate more deeply than big, fat handgun slugs.

The geometry of the bullet (not to mention any deformations it undergoes) plays a large role in determining how much energy it loses as it progresses through the body. Ideally, you want all of its energy to be released without it exiting the body.

So, any formula you use to ask which energy configuration is better will probably have to take geometry (size) of the projectile into account. One such system is the Taylor Knockout Value.

Read about it here

By the numbers, a .44 Magnum should have a better "knockdown potential" than a .308. (Not a result I would've expected!)

[elSquid]

You know, I bet with enough real world testing you could accurately come up with a mathematical formula that explains cavity creation.

I really suck at math, so I wouldn't be the one to make such a thing, but it's possible.

Probably. But it wouldn't be simple. I certainly don't have the math for it either.

Since it hasn't been done yet, I guess people don't see it as something necessary.

Probably not cost-effective. It's much easier to just take the rounds of interest, shoot a bunch of gel blocks and see what happens.

And of course, if you want to be particular, ballistic gelatin only gets you so far. After all it's not the "real thing" either.

-- Michael

[1911su16b870]

The motivation of the target is a variable. Very motivated adversaries can be bullet sponges and keep fighting.

[locosway]

The "linebacker" analogy of "energy dump" is not apt because it neglects that (1) the time involved in the collision of a bullet with a body is much, much shorter; and (2) the interacting areas are much, much smaller.

We all know from high school physics that energy is the ability to do work. No energy, no work. Displacing body tissue from its equilibrium position is work. So do two bullets with the same energy do the same damage even if their mass and velocity values are different?

Probably not. A bigger diameter bullet impacting a body will act on a larger cross section of tissue than a smaller diameter bullet will. This should serve to "drag" the bullet's speed down more rapidly and keep it from penetrating deeper. This somewhat follows our common sense that higher speed rifle bullets penetrate more deeply than big, fat handgun slugs.

The geometry of the bullet (not to mention any deformations it undergoes) plays a large role in determining how much energy it loses as it progresses through the body. Ideally, you want all of its energy to be released without it exiting the body.

So, any formula you use to ask which energy configuration is better will probably have to take geometry (size) of the projectile into account. One such system is the Taylor Knockout Value.

Read about it here

By the numbers, a .44 Magnum should have a better "knockdown potential" than a .308. (Not a result I would've expected!)

I guess the TKO is the same idea I had, just different ways of coming up with the number.

I posted my site on THR and unanimously it was ripped down as being crap. Now, I'm not sure why, and no one could give me a good suggestion. They just simply said no.

I'm still not convinced that this method will not work for showing a rounds potential. It uses the same math formulas that everyone in the world uses to calculate expected terminal performance, so what's so terrible for showing it in simpler terms?

[B Strong]

I'm curious about something.

Would you say that a:

.44 Magnum 300gr @ 1350 fps

and a:

.308 147gr @ 2750 fps

Would do the same damage, transfer the same energy, and penetrate the same, if shot at a soft target at a distance of 10-15 feet approximately?

I don't want to incite any riots, but I've been working on something, and my data leads me to believe that they're equal under the terms I've listed.

They're not "equal"

The 300 grain .44 is going to have a wider meplat, the .308 is going to be a spire point.

The 300 grain .44 is going to shed more velocity during penetration than the .308.

The wider wound channel of the .429 diameter projectile is going to cause more tissue damage than the .308 diameter projectile.