Bullet Caliber Comparison

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gdeal

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Why is a .38 considered so lame and a .40 considered half way decent?
The difference is only .02
 
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I don't think the .38 is considered lame. I think it just goes back to the saying "shoot the biggest caliber you are comfortable with."

My 15 oz. snub nose .38 carries easily and shoots semi-pleasant. I would not want to shoot the .40 from the same size gun.

Oh, and the difference is actually .043 since the .38 bullet is .357 in diameter.

EDIT: The .38 is probably considered "lame" when talking about duty weapons. Why carry 6 .38s going 900-1000 fps when you can have 15 .40s going 1100 fps?
 
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the difference is actually .043 since the .38 bullet is .357 in diameter
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I never knew that. That would explain why .38's and .357 Magnums can be fired from the same revolver a lot of the times.

But why do they call it a .38 then if it is really closer to a .36 ?
 
The difference is .043" because the .38 actually measures .357". Also note that you are comparing linear diameter of the bullet. Take that linear diameter and compute area of the circle, then multiply by the length of bullet to get volume and then consider the velocity. One measure of energy equals bullet weight (mass) times velocity squared.
 
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I never knew that. That would explain why .38's and .357 Magnums can be fired from the same revolver a lot of the times.

But why do they call it a .38 then if it is really closer to a .36 ?
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Probably marketing. Note 9mm is also around 0.355 inches in diameter. So lots of rounds around the same diameter reduces confusion to call them slightly different things. Same reason 0.40S&W is not called 10mm even though it is.
 
Take that linear diameter and compute area of the circle, then multiply by the length of bullet to get volume and then consider the velocity. One measure of energy equals bullet weight/mass times velocity squared.
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Professor, it sounds like you have a PhD in this.
 
Same reason 0.40S&W is not called 10mm even though it is
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Wait a minute. I thought the 10mm was bigger more powerful than the .40 S&W. You are saying it is the same size though? Or just the same size diameter?
 
I don't think its a lame round, wouldn't want to get hit by one thats for sure. And
.40 considered half way decent?
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I'd consider a .380 halfway decent, .40 is a very capable round, I've seen the damage up close...its not pretty.
 
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If they were both six shooters I bet you wouldn't hear that as often. I think it's a matter of capacity of the platform.
 
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Same reason 0.40S&W is not called 10mm even though it is
Wait a minute. I thought the 10mm was bigger more powerful than the .40 S&W. You are saying it is the same size though? Or just the same size diameter?
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It is the same diameter bullet, the 10mm case is longer and holds more powder. To prevent confusion S&W called the new cartridge the 0.40 S&W instead of 10mm short or something like that.

Good chart on many of the different English and metric size bullets on Wikipedia

http://en.wikipedia.org/wiki/Caliber
 
gdeal said:
I never knew that. That would explain why .38's and .357 Magnums can be fired from the same revolver a lot of the times.

But why do they call it a .38 then if it is really closer to a .36 ?
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In the 1800's alot of the bigger bore rounds were step heeled bullet designs like the .22 is still. That meant the actual bullet was the same diameter as the outside of the case, like the .22.

If you measure a .38 special case, you'll find that the outside diameter at the case mouth is .380. or 38 caliber. When the ammo companies started switching to what is known as outside lubricated bullets, the type we see today, wherein the bullets actual diameter is the same as the part that fits inside the case, they stuck with the original caliber designation of the outside lubricated bullets of the earlier rimfire, and step heeled bulleted rounds. Thus ".38". The .38 special was developed back around the turn of the last century, and some common practices were still in use then like calling a round by the outside dimension of the case. There's a little more to the story, but that is the gist of it.
 
Because most people believe crap they see on the internet and read in gun magazines and don't know about real life shootings in their own area.

The .40 is issued to a lot of LE agencies in my county and surrounding counties and has been involved in a LOT of shootings. I don't know of a single one which is a one-shot stop scenario and most are what you would consider failures.

Guy shoots himself in the leg and drives to the hospital when loading his .40.

Cops shoot a guy 7 times with .40s and have to whip on him with flashlights and pepper spray him to keep him from continuing to fight them, etc....

On the other hand, I know of some .38 stopping failures too.
The thing is, I know of a lot of .38 shootings where it did the job. Can't say that for the .40.

Ballistics charts don't often tell the whole story. As for the extra bullet weight and velocity, that reminds me of something Jeff Cooper once opined about the .44 magnum. Cooper noted that the full bore load seemed to whistle right through a bad guy without making any more impact than a hot .44 special.
 
Why is a .38 considered so lame and a .40 considered half way decent?
The difference is only .02
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The .38 Special pushes a smaller, lighter bullet at lower speeds. There's a lot of argument over whether it's more important that the bullet be fast, or heavy, or wide, and why, but the .38 Special winds underperforming on all three points relative to the .40S&W.

.40S&W catches a certain amount of flack for being a cut-down version of 10mm Auto, which is considered the Best Pistol Cartridge Ever by some parties. I'm not a fan, but I favor 9mm Luger for lighter recoil, personally.
 
Just my guess. Neither caliber, or 9mm for that matter, is going to stop a drunk, cranked up bad guy, without a CNS hit. Something like 95% of all crimes are done under the influence, that is for the ones that get caught.

So, we are left with shot placement. I do think the .40 S&W suffers from poorly loaded ammunition, with powder not tailored to it's specific use. It seems people complain of excessive recoil, since it recoils about 100% more then 9mm.
Case is near twice as big as 9mm.

Anyway, accuracy is easier with a low recoiling gun, and, most police aren't the greatest shooters, so, a low recoiling gun, like a .38, is more likely to be placed percisely then a .40, if they find it recoils too much.

Elmer Keith and Skeeter Skelton went through the same sort of progression with revolvers that we are currently with semi-autos.
They started with hot .38's, and the .357 was born. That wasn't enough in some situations, so they came up with the .41 Magnum. As is the problem with the .40 and 10MM, the .41 recoiled too much for your average cop, and,
the guns were big and heavy. Result was the .41 'police loads' were so low power, there wasn't much point to having the .41 over the .357. Same with the .40 S&W, compared to the 9mm.

For people that do shoot, the 10mm and .41 Magnum, loaded properly, give a huge advantage over the .38.

One of the best resources on the web is this site:

http://www.ballisticsbytheinch.com/38special.html

by one of the members here. It gives you a real good idea at what barrel length different factory offerings give decent ballistics, vs. other calibers. You might find that some of the .38 special loadings are pretty potent.

Also keep in mind that the .38 is a pretty big case, compared to the .40, and, it's possible to come up with plus P loads that are right on the heels of some of the .357 Magnum loads.

I've chronographed three loads for my .357 1.8"
barrel.
Corbon 125 grain at 1200 fps, 357
Fioochi 148 grain @ 1131 fps, 357
Buffalobore .38 Plus P 158 grain, 1040 fps.
 
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Why is a .38 considered so lame and a .40 considered half way decent?
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The real difference isn't bore at all - it's muzzle energy.

This table is your friend:

http://www.naaminis.com/energy.html

Let's use Winchester for comparison. Their best 38+P load is the 130gr Supreme +P, which is a pretty damned good round, among the top 10 most effective 38 combat loads. They claim 925fps (feet per second) at the muzzle from a 4" barrel, so that's about 250ft/lbs energy.

Winchester's best 40S&W series is likely the 165gr T-series:

http://www.winchester.com/products/...symbol=S401&cart=NDAgU21pdGggK0FDWS0gV2Vzc29u

Per NAA's chart, 165gr doing Winchester's claimed 1130fps gives us about 465ft/lbs energy - damned near double the 38. The very best .40S&W ammo from smaller more radical ammo houses like Doubletap and Buffalo Bore hits almost 550ft/lbs of energy; their best 38+Ps hit over 350ft/lbs energy.

In comparison, in my 357Mag gun I carry Doubletap's nasty full-house 125gr slug doing better than 1,600fps in my gun (4.68" Ruger New Vaquero) for over 750ft/lbs energy. And yeah, it's "all that" - this is the stuff I blew up a bowling ball with once at 20 paces, split it in half and sent fist-size chunks of the concrete core back past my feet. (A bowling ball turns out to be concrete surrounded by about an inch of plastic.) The guy whose range that was and who used old bowling balls as targets said he'd NEVER seen that sort of action out of a handgun, ever, in any caliber.

The only guy who tops Doubletap (by a little in most calibers) is Tim Sundles at Buffalo Bore, probably one of the finest specialty ammo brewers ever.

You'll get differing opinions as to whether or not that energy is going to be used. If it hits nothing but soft tissue, it's going to blow on through and there won't be anywhere near total energy transfer to the target. However, if it hits relatively delicate tissue such as the liver, kidneys or spleen there could be pretty serious disruption. The possibility for serious damage happens when you hit bone on entry to the upper torso...hit the sternum or a rib and you've got enough power on tap to shatter it and send pieces of bone through the upper chest as secondary shrapnel and yeah, that's gonna hurt :eek:.

Speed also means hollowpoint expansion is more reliable.

However, the .40 will likely expand a bit fatter and there are people who believe that's THE key factor as long as you also have enough energy to punch deep.

The best 38+P slugs will expand to about .55" or so and punch about 12" deep - the Speer Gold Dot 135gr +P will do this most of the time, as will the better 158gr all-lead +P hollowpoints. My Doubletap 125s will likely expand to .65 or so and punch deeper, while the best .40s will expand past .70" by a bit.

What else...

The .40 came about because the FBI wanted something hotter than the 9mm after that round was blamed (unfairly in my opinion) for a shooting that went very bad in Miami in 1986:

http://www.thegunzone.com/11april86.html

So they went to the 10mm which is .40cal wide and almost as hot as the 357. They ran into two problems: some agents didn't like the recoil and the early S&W guns started literally cracking. So they loaded the 10mm with less powder, ran reduced power recoil springs in the same guns and solved both problems, but that left them with guns that were oversize for the horsepower used. Somebody at S&W realized you could shorten the 10mm to 9mm shell length and use the new shorter 10mm (loaded the same as the "10mm lite" loads) in smaller, handier guns that better fit the hands of smaller and/or female agents. And thus was born the 40S&W, basically as a result (over several steps) of the Miami shootout.
 
The real difference isn't bore at all - it's muzzle energy.
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And, muzzle energy as a measurement isn't without flaws either. Energy measurements tend to place a higher value on speed than on mass which then leads you down the heavy/slow vs fast/light debate.

I'm not taking away from Jim March's post by the way, its well written, I'm just showing that a lot of this cartridge over that cartridge is subjective at best.
 
Krezyehorse said:
Quote:
The real difference isn't bore at all - it's muzzle energy.

And, muzzle energy as a measurement isn't without flaws either. Energy measurements tend to place a higher value on speed than on mass which then leads you down the heavy/slow vs fast/light debate.

I'm not taking away from Jim March's post by the way, its well written, I'm just showing that a lot of this cartridge over that cartridge is subjective at best.
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+1
The faster an object moves, the faster it tends to slow down. If you are only shooting at bare or lightly covered skin, then speed is going to be a big help, but if you have to go through a lot of layers of clothing, a door, or car body, I'll take heavy at decent velocity every time over all out speed.

One thing that is in the .40's favor is the fact that is already larger in diameter than the .38. The only real world way to increase killing power in relatively weak handguns is to increase bullet weight and diameter. Energy doesn't kill. Penetration of vital organs kills, and that requires momentum which favors heavier weight, construction being equal.

I have used this illustration several times in the past when someone tries to declare that energy is all important.

My 22-250 will turn up higher energy numbers using factory ammo than a 45-70. Which would you want to have in your hands to stop a charging big game animal, bear or otherwise?
 
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