380 vs 9mm size..

[Barms 98]

so the smaller carry guns that are in 380...

 

obviously the LENGTH of the cartridge is smaller than a 9mm..   but width of the BULLET I believe is the same (someone talk to me about grains please).   Now I think the width of the CARTRIDGE is "slightly" wider?    so if bullet is the same width but cartridge is wider then its about how the bullet is pressed in the cartridge, is that right?

 

so anyway here is what I'm really wondering about..   are the 380 guns smaller because they even make the GRIP shorter/thinner since the round is shorter?  so like they are making use of all the smallness of the 380 to make the gun smaller?

 

If the grip was not shorter (I mean front to back not length of grip) than a 9mm then are they choosing 380 just because the cartridge is slightly thinner?  I mean its negligible..

 

Im just thinking these things in the debate of a 380 vs 9mm carry gun.

 

so just summary..  380 shorter = smaller grip = smaller gun?    Or is size of the grip the (front to back) the same on a 380 vs a 9mm?

 

 

[robot_hell 72]

The 9mm is a tapered cartridge, and .380 ACP is straight wall. The cartridge rim dimensions are different as well. This is why you would not be able to use the same reloading dies for 9mm and .380, for example. Here's a close-up that shows it clearly: http://www.personaldefensenetwork.com/wp-content/uploads/2014/01/caliber-comparison.jpg

 

You are correct that the bore size (diameter of the barrel) is the same for both guns. In fact, on some guns you might see the .380 ACP referred to as the 9mm Kurz, or the 9x17mm. Similarly, 9mm Makarov is 9x18mm, and 9mm parabellum (the one most people know as 9mm) is 9x19mm.

 

Here's one ballistic comparison using two pocket guns that come in both calibers. There are many similar comparisons out there, and even more debate to go with it:

http://www.taurusarmed.net/forums/attachments/factory-loads/56789d1369923041-ballistic-gel-comparison-380-v-9mm-results-surprised-me-comparison-.380-v-9mm-hornady-defense.jpg

 

With modern machining and firearm design, the newest 9mm guns really do come close to-- if not match-- the size of .380 pocket guns. For older designs, the size difference was mainly because of a different action: 9mm pressures require the use of a locked breech, whereas the pressure of a .380 is low enough that a simple blowback mechanism (and a stout recoil spring) is sufficient to prevent the breech from opening too quickly. That means a lightweight blowback .380 may have more perceived recoil than a locked-breech 9mm. With less moving parts and less precision required, the blowback design could be made smaller and more reliable.

 

Today you'll find most pocket pistols in .380 ACP sporting the same Browning locked-breech action as their larger brethren, which softens the recoil and makes it easier to rack the slide. The trade-off is accuracy, which usually isn't a factor in considering a small carry gun for personal defense.

[Krdshrk 3,877]

9x19 (9mm) Dimensions:

 

Bullet diameter 9.01 mm (0.355 in)

Neck diameter 9.65 mm (0.380 in)

Base diameter 9.93 mm (0.391 in)

Rim diameter 9.96 mm (0.392 in)

Rim thickness 1.27 mm (0.050 in)

Case length 19.15 mm (0.754 in)

Overall length 29.69 mm (1.169 in)

 

.380 ACP Dimensions::

Bullet diameter .355 in (9.0 mm)

Neck diameter .373 in (9.5 mm)

Base diameter .374 in (9.5 mm)

Rim diameter .374 in (9.5 mm)

Rim thickness .045 in (1.1 mm)

Case length .680 in (17.3 mm)

Overall length .984 in (25.0 mm)

 

 

.380 ACP uses the same size bullet (.355) but generally lighter - 85-95gr instead of 115-147gr (usual loads for 9mm).  The cartridge measurements are a bit smaller than 9mm.

 

[djg0770 481]

Bullet weight is expressed in grains.  380 bullets are typically 90-95 grains in weight (7000 grains in a pound).  9x19 (9mm Luger) bullets are typically 115-124 grains.

 

Sure it doesn't sound like a lot, but that translates to 27-37% more bullet weight.  In addition, the 380 round generally tops out at 1000 ft per minute (fpm) velocity whereas the 9mm starts at 1200 fpm and goes to around 1400 fpm.

 

If you use the simple formula of mass times velocity, you see that 95 gr * 1000 fpm = 95,000 (never mind about unit conversions right now) and 115 gr * 1400 fpm = 161,000 ERGO (waves magic math wand) that's about 70% more energy available in the 9mm bullet as it leaves the muzzle over the 380.

[Barms 98]

Most excellent data above.

 

Can someone chime in about the size of the GUN though? Is the grips smaller on a 380 gun because the round is shorter?

[bhunted 887]

IMHO, not noticable. But it depends on the gun. Take a look at the Sig line... P938 vs. P238...

It's not sizable enough to be concerned. If you are looking at a particular model and can only find it in 380, (or what they call 9mm Kurz<(short), then with the newer 380 ammo, you'd be fine. But I prefer a 9mm as to not have to have so many different calibers to rely on. Chances are most of us have a 9mm of some sort. The Sig P938 Extreme is on my very short list.

 

Sig P938 Nightmare: http://www.sigsauer.com/CatalogProductDetails/p938-nightmare.aspx

Sig P238 Nitron: http://www.sigsauer.com/CatalogProductDetails/p238-nitron.aspx

 

938 vs 238 length is the only difference and the 938 comes in at .1" longer in length...They are both built on the same design...

[xkon 0]

Bullet weight is expressed in grains.  380 bullets are typically 90-95 grains in weight (7000 grains in a pound).  9x19 (9mm Luger) bullets are typically 115-124 grains.

 

Sure it doesn't sound like a lot, but that translates to 27-37% more bullet weight.  In addition, the 380 round generally tops out at 1000 ft per minute (fpm) velocity whereas the 9mm starts at 1200 fpm and goes to around 1400 fpm.

 

If you use the simple formula of mass times velocity, you see that 95 gr * 1000 fpm = 95,000 (never mind about unit conversions right now) and 115 gr * 1400 fpm = 161,000 ERGO (waves magic math wand) that's about 70% more energy available in the 9mm bullet as it leaves the muzzle over the 380.

 

Feet per minute eh?  Didn't know I could outrun a 380 and 9mm lol.  I believe you mean FPS (feet per second)

[Shocker 150]

If you use the simple formula of mass times velocity, you see that 95 gr * 1000 fpm = 95,000 (never mind about unit conversions right now) and 115 gr * 1400 fpm = 161,000 ERGO (waves magic math wand) that's about 70% more energy available in the 9mm bullet as it leaves the muzzle over the 380.

 

No, your equation says it has 70% more momentum.

 

If you square the velocities to actually get energy you're looking at 137% more energy

 

The units don't matter anyway bc when you divide for the percent increase all units drop out

[robot_hell 72]

Didn't know I could outrun a 380 and 9mm lol.

[Pizza Bob 1,488]

Yes - a smaller physically dimensional round allows for a smaller physically dimensional gun. Pretty much common sense. What I haven't seen anyone mention is the recoil impulse generated by the respective cartridges.

 

Since we are talking about defensive handguns, second shot capability (recovery from recoil) is important. In a lot of cases the recoil impulse generated by a .380 handgun will be more severe than that generated by a 9mm. Two reasons: 1) Less mass of the smaller gun to dampen the recoil; and, 2) Most .380 handguns - especially the smaller ones, use a blowback action. Most 9mm handguns use a locked breech action which delays the recoil impulse and uses some of the energy created to unlock the breech, thus making the 9mm easier to control.

 

.380 bullets usually run in the 80 to 100 grain range. Common bullet weights for the 9mm are 115gr, 124 gr and 147 gr - 124 gr is the NATO standard.

 

Adios,

 

Pizza Bob

[High Exposure 5,662]

Like PB said, yes - a smaller round means a smaller pistol grip on standard configuration semi-autos ie: magazine in grip design. However, there becomes a point where the grip is just too small - this falls under "Just because you can doesn't mean you should". Both 9mm and .380 pistols could be made smaller still, but you reach a point of diminishing returns.

 

I have found that generally anything smaller than a single stack 9mm size grip - think Kahr PM9 size - is less than desirable in a gun that's to be used for defensive purposes, again for the reasons PB stated above.

 

Those small .380s are hard to shoot - not that you can't get good at it, the juice just isn't worth the squeeze when you can get a 9mm in the same size package.

 

Drives me crazy when someone says they are going to get a Ruger LCP/S&W Bodyguard for their wife/daughter/girlfriend because they think 9mm is too much and .380 is easier to shoot, and a smaller gun will "fit their hand" better.

 

Back in the day, the only way to get a small gun was small calibers. The .25ACP then is the size of a .380 now. A .380 then is the size of a modern 9mm or even .40 now. Hell, we have modern 9mm pistols the same size as modern .380s now. The material science back then just wasn't capable of what it is today.

[Barms 98]

Great replies. Now I have all bullet size plus the gun size considerations answered

 

Good job.

 

Just for the record. Original idea was mostly inquiry about the gun size and the 380 but the knowledge about the blow back stuff was great

[JackDaWack 2,895]

Like PB said, yes - a smaller round means a smaller pistol grip on standard configuration semi-autos ie: magazine in grip design. However, there becomes a point where the grip is just too small - this falls under "Just because you can doesn't mean you should". Both 9mm and .380 pistols could be made smaller still, but you reach a point of diminishing returns.

 

I have found that generally anything smaller than a single stack 9mm size grip - think Kahr PM9 size - is less than desirable in a gun that's to be used for defensive purposes, again for the reasons PB stated above.

 

Those small .380s are hard to shoot - not that you can't get good at it, the juice just isn't worth the squeeze when you can get a 9mm in the same size package.

 

Drives me crazy when someone says they are going to get a Ruger LCP/S&W Bodyguard for their wife/daughter/girlfriend because they think 9mm is too much and .380 is easier to shoot, and a smaller gun will "fit their hand" better.

 

Back in the day, the only way to get a small gun was small calibers. The .25ACP then is the size of a .380 now. A .380 then is the size of a modern 9mm or even .40 now. Hell, we have modern 9mm pistols the same size as modern .380s now. The material science back then just wasn't capable of what it is today.

Right. I had to put the rubberized grip on my P938 just to shoot it enjoyably. I wouldnt buy anything smaller then that, and my hands are medium in size. You cant pocket carry it, but you could conceal it very easily.. no reason to go smaller with so many good 9mm option now.

[carl_g 568]

I am far from a glock guy but I have a g42 and it is great. I can make the ammo for pennies and shoot it all day comfortably. The follow up shots are easy to control as the recoil is minimal. I know it is big for a 380 but still the weight and the ability to control make it easy to carry and also to shoot. The latest new tech 380 ammo is pretty bad ass. I would not want to be hit with it..that is for sure.

[Pizza Bob 1,488]

I am far from a glock guy but I have a g42 and it is great. I can make the ammo for pennies and shoot it all day comfortably. The follow up shots are easy to control as the recoil is minimal. I know it is big for a 380 but still the weight and the ability to control make it easy to carry and also to shoot. The latest new tech 380 ammo is pretty bad ass. I would not want to be hit with it..that is for sure.

 

For years (maybe still) the 9 mm Kurz was a common police round in Europe. With today's high performance SD ammo, it can be an effective fight stopper. Your Glock has a locked breech so easy to control.

 

Adios,

 

Pizza Bob