General question on bullets


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Enron Exec
November 13, 2007, 12:23 PM
Hi guys,

I was just wondering what makes a rifle round so much more effective in "stopping power" then a pistol, assuming a none CNS hit. Do rifle rounds create such TC that they can damage nerves to better incapacitate? The reason i ask is because i was just pondering why there isnt a small caliber pistol round with near rifle velocities to create this type of TC. Is it because there is no powder to push a say, .30 cal 55-80 gr bullet to ~2000 f/s in 4"-5" barrel? After practicing with a P226 in 357Sig for about 3 months, i find the recoil can be managed and i prefer that over higher muzzle flip found in larger heavier rnds like the .45 ACP. It then struck me there is the 5.7 x 28mm. So how effective is this .224 cal in its 28gr 2300 f/s HP and its other varieties at being a man stopper? Does it show some of the effects of a 5.56 55 gr? The 5.7 was originally designed around to pierce soft body armor for submachine guns for LE but is the civilian HP version any good? From my limited understanding id think it would be interesting to see a fast small cal rnd for full size handguns. Or am i way off on this thinking? So hypothetically speaking, assuming there existed a powder that could propel something like a .30 cal 80 gr good HP bullet to some 2000 f/s in a 5" barrel, ruffly 710 ft-lbs, would that be an effective pistol cartridge for self defense? Could the recoil be managed w/ alot of practise? Would a well designed gun chambered in such have considerable muzzle flip? This is all just for academic debate. :)

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Acheron
November 13, 2007, 12:31 PM
The hypothetical cartridge you're describing sounds a lot like 7.62x25 TT. They are loaded with bullets ranging 75-90gr and can approach 1600 fps and can penetrate most Type II vests. Most of the new small-caliber pistol rounds (5.7x28 FN and 4.7x30 HK) are based on the principles outlined in the 7.62 TT. The 7.62 TT itself was based on the earlier 7.63x25 Mauser cartridge used by famous pistols like the C96.

To answer your question, a 80gr HP traveling 2000 fps with 710 ft/lbs would be an effective SD cartridge. The TT (I'll admit it doesn't quite meet the OP's specs) has been stopping men more than 70 years now.

SaMx
November 13, 2007, 12:48 PM
rifle rounds are going much faster and have much more energy than pistol rounds. They have more stopping power simply because they are literally more powerful.

Enron Exec
November 13, 2007, 01:09 PM
I just wiki it up and yes, the 7.62x25 Tokarev is exactly what i was looking for. But yea maybe it could be possible to make a newer faster version using today's technology?

So if someone had the financial backing and wanted to make a one off prototype cartridge and full size handgun to satisfy their curiosities, what would you think would be the ideal balance for a say 7.62x25 +P sort to speak? What changes would you make?

Thanks for the great responses. :D

loose cannon
November 13, 2007, 01:26 PM
this could be the next thing in the advancement of defense handguns,,,

the only thing is what i call the"everything has a pricetag"rule.to get the numbers you want with our current technology(that i know of lol)you will have to pay the price in preasures and gun wear as well as recoil.

it may be possible to do it more effectively when we have new and more efficient propellents that can give increased velocitys without the monster preasures

make mine integrally suppressed cause the blast will be a bear

Acheron
November 13, 2007, 01:29 PM
To be honest, you don't want to make 7.62 TT too much more powerful. I've shot several hundred rounds through my TT-33 and the recoil is surprisingly stout for such a 'small' cartridge. This is using Romanian surplus and a little S&B. For the record, Czech-produced ammo is usually quite a bit hotter than most and is only meant for CZ 52 pistols.

As far as changes to the 7.62 TT, in order to reach the performance that has been outlined I would do two things:

1) Change the bullet to a 70-75gr FMJ with a hardened steel core (or JHP for SD)

2) Increase the powder charge by a few grains (2-3)

The powder charge would have to be tweaked to get the right performance, but I think that it could be done. The pistol would definitely have to be full-size and well built to handle what is approaching the characterisitcs of a small rifle round. The problem is that recoil could be prohibitively severe unless the pistol weighed a ton (which is another disadvantage). I'm not sure how successful a 7.62x25 '+P' would be.

Enron Exec
November 13, 2007, 02:11 PM
I see, a Czech 85 gr pushed to 1600 f/s produces a nice 483 ft-lbs. Now im intrigued to find a CZ 52. The S&B practise ammo looks to be very affordable as well.

Still though i found that Cor-Bon makes a 115gr 1500 f/s 357Sig that will produce 575 ft-lbs.

Hmmmm.. how does one go about testing new hand loads? I know very carefully, but has anyone tried this on their own? Any good books on how to approach this? :)

loose cannon
November 13, 2007, 02:15 PM
doing your own load concoction is like being a test pilot on new designs that never flew.if all goes well then youre ok but if it doesnt,,,,

crash and burn with gunparts embeded in your body.

ill pass

Phil DeGraves
November 13, 2007, 03:26 PM
Rifle rounds function differently than handgun rounds for a number of reasons. The velocity factor is one of those reasons but the velocity has to be in excess of 2600 fps to really reap the benefits of hydroelastic impact. Most rifle bullets have a much superior ballistic coefficient and sectional density than handgun bullets. Now while the ballistic coefficient (or how easily a projectile slips through resistance) may actually be inversely proportional to the impact effect on a soft target, the sectional density (which affects the ballistic coefficient) is directly proportional to its impact effect. The high ballistic coefficient allows rifles to deliver accuracy at greater range with less loss of velocity than pistol bullets. The higher sectional density allows the projectile to keep driving through the target after impact, what British ballisticians have commonly called "transmission dwell". You see it a little bit with British cartridges like the 455 Webley which, for a pistol cartridge haa a pretty good sectional density though still not anywhere close to most projectiles intended for rifles.

John Caile SDI
November 13, 2007, 04:27 PM
Acheron said: "a 80gr HP traveling 2000 fps with 710 ft/lbs would be an effective SD cartridge"

Well, would it? The answer (as in most questions regarding ballistics) is:

Maybe.

The dynamics of "stopping power" (more accurately described as immediate incapacitation) are more complex than mere numbers. Energy in itself guarantees little.

For example, I've seen a man in a Level V Kevlar vest take a point blank hit with a 12-gauge slug. How much energy was "transfered" to him? All 2,500 ft. lbs. of it. The result? Nil. Zip. Nada. He flinched and said "Damn!" but didn't move an inch, nor did he suffer any harm (other than a big bruise on his chest). Yet if I stick my $4 knife from the bargain bin into the base of your skull ("transferring" about 8 or 10 ft. lbs of energy), you will drop like a stone. What counts is not energy per se, but rather how the energy is used, i.e. how much damage it does.

Now, a very large Temporary Cavity can indeed do substantial damage, IF it is sufficiently large to exceed the stretch capacity of most human tissue (which, with the exception of the liver and a few other organs) is VERY elastic. Normally, this limit is NOT reached by bullets traveling as typical (800-1600 fps) pistol velocities.

Can such velocities be achieved with bullets fired from pistols? Well, yes, but here's the rub: you have to scale down the bullets to such tiny dimensions (and such ultra light weights), that the resultant T/C created by such a tiny pistol round (the 23 gr. FN 5.7 for example) is proportionally much smaller, and therefore less effective, than say, a 150 gr. 7.62 NATO round at a similar velocity. Also, many of those "magic bullets" that are advertised generally use NON-elastic media like clay to show "explosive" expansion (or they shoot a bunch of goats, which, the last time I checked, are not likely to be angry, drunk, or high on Meth!).

We can debate the light-and-fast versus heavy-and-slow forever (and probably will!), but several hundred years of history has suggested that we should carry whatever gun we can carry comfortably that reliably fires the largest caliber bullet we can shoot competently.

Me? After 45 years of shooting, hunting, and after reviewing over 200 after-action reports of police shootings, I carry either a Sig P220 (45ACP) with 230 gr. Golden Sabre JHP's, or my Glock 20 (10MM) with 180 gr. Double Tap Gold Dot JHP's.

At the end of the day, the primary determinant of our survival will be our awareness of what's going on around us, and our ability to put 2 or 3 rounds where they count before an assailant can kill US.

Stay Safe!

Acheron
November 13, 2007, 04:44 PM
John brings up a very good point. At the end of the day, the caliber really doesn't matter nearly as much as YOU do. If you are comfortable with a .45, then shoot .45. If you can't handle/don't like it, then use something else. It all comes down to determining the threat and acting appropriately before harm can come to yourself or another. The rest is merely details.

nplant
November 13, 2007, 07:49 PM
John just about nailed it for the "real world" answer.

But for fun, remember that even if you have "enough" powder to do what you think will happen, the barrel length might just end up venting a red giant of a fireball, and that does nothing for velocity or energy (with respect to the actual projectile). In other words, you can put enough powder to theoretically accelerate the bullet to around 2000 fps at the muzzle, but if the powder is not efficiently burned, you negate the use of so much, since it will exit the muzzle unburned, and therefore useless as far as the bullet's peak velocity is concerned.

Also remember that rifle rounds generate more pressure than pistol rounds (by necessity) and you need a gun that can safely contain that higher pressure in order to benefit from the byproducts of that pressure.

Good luck, but I wouldn't recommend chasing this one.

TauZero
November 13, 2007, 07:50 PM
Try looking at energy another way. Say you have two bullets, a .17 and a .45. If their velocities are different, it would be possible for both of them to have the same amount of energy, let say 300 ft-lbs. But if you were hit by a .17 with 300 ft-lbs of energy the damage done would be very different than the .45 with 300 ft-lbs of energy.

The point is that energy alone, just as bullet size alone, are not necessarily the best indicators of stopping power. As others have said, find a gun you like and get good with it. This is far more important than its caliber and power.

Tyris
November 13, 2007, 08:09 PM
I've carried a cz-52 before. It conceals easily as it is as slim as a 1911. Recoil is easily tamed with a heavy recoil spring, I use 18 pounds and it stops the frame from getting battered. Mine has been super reliable (aside from the first firing pin I broke, now long since replaced).

The FMJ round itself rocks, it zips through TVs, empty propane cans, computers with incredible penetration that I've found in no other pistol caliber. This round out of a PPSh-41 is fun :D

I'd love to see after market barrels (new steel with new rollers) for it, and Im hoping that Makarov.com can eventually score some. I'd pay $1000 in a heartbeat for a new production cz-52 made from stainless steel. Heck, any new production pistol in that round would be excellent (glock, sig, CZ, you listening??) :eek:

-T

Cosmoline
November 13, 2007, 08:24 PM
Do rifle rounds create such TC that they can damage nerves to better incapacitate?

Yes. The temp. cavity generated in flesh of a 150 grain rifle round at beyond the @2,300 fps threshhold is substantial enough to cause serious secondary damage and make the shock worse. It's the so-called "explosive" effect.

http://www.barnesbullets.com/videos/308_180gr_TSX_6fps_logo.wmv

The tok and other high velocity handgun rounds are only high velocity compared with other handgun rounds. None of them are cooking at 2,600 fps or 3,000 fps out of short gun (maybe a thompson center I suppose). To even come close you've got to shrink the bullet down and the pressure up, so you end up with a lot of blast and flash and a wee bullet. The small bullet reduces penetration and also limits the amount of direct damage, so it's a tradeoff. In the end a lot of folks have just decided to stick with traditional big n' slow handgun rounds tand rely on direct bullet-to-cell tissue damage. Even with rifle rounds such as the .223 or .224, the smaller bullets limit the amount of damage even at ultra high velocities. The original recipe of a 6.5mm to 8mm expanding bullet at 2,300 to 3,000 fps seems to be the most lethal medicine a small arm can dish out without resorting to very large cartridges. Get much bigger and recoil goes up while velocity goes down. Get smaller and velocity goes up but the bullets get too small to be reliable stoppers.

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