9mm vs. .45 overpenetration....

D

Don Gwinn

Staff Emeritus
I don't know a ton about handguns and I'm looking for my first defensive semi-auto. I've already decided I want a CZ-75 or a CZ-97. I live in a townhouse apartment with units on each side, so I'd like to minimize the chance of penetrating a wall with a miss.

I'd like a .45, but I reason that with a more massive bullet, even at slower speeds, the .45 is probably more likely to penetrate my walls than the 9mm when both come out of a 5" barrel. Is this true? If both will readily penetrate standard interior walls, or if neither will, then I'll probably get the .45 despite the cost. Thanks.
 
Well, if you are talking two layers of sheetrock with some insulation between them I suspect that either one in FMJ will go right through them. In HollowPoint? dunno, but the 45 does have greater cross-sectional density which is the main determinate in penetration.

This means that WHATEVER the bullet goes through (glass, door, leather jacket, forearm, etc.) the 45 is more likely to retain more energy and penetrate further. This can be a good thing if you need the penetration to save your life and kill a bad guy, or a bad thing if you cleanly miss and your neighbor's daughter is just on the other side of the wall.

Like everything in self-defense shooting, placement is EVERYTHING. If you place a bullet to hit a bad guy, then overpenetration is probably not going to kill any neighbor through your walls. If you place a bullet at a weak part of the wall at an angle that could hit a neighbor, then it probably doesnt matter whether its a 9mm or a 45.

Now practically speaking:
Lets say, for the sake of argument that you WANTED to hit your neighbor through your walls. you dont know where they are, and you are only going to have enough time to fire 2-3 bullets. and those bullets have to be in a ten foot circle that I draw on your wall. Now what are your chances of hitting them? Pretty darn slim. Does it happen? RARELY. Usually the people that get hit by bullets through walls are inside a house that gets riddled by driveby shootings.

My decision has been to defend me and my family as best as I know how. I shoot regularly, I familiarize my family with firearms and teach them firearm safety, and I make sure that my firearms are kept in safe, secure locations.

I also shoot .45acp.

J.T.

As usual, FWIW, IMHO, YMMV and all that...
 
Either one in FMJ will go through interior walls, but I think 9mm tends to penetrate more than 45. In your scenario, I think fragmenting ammo (Magsafe, etc) would be a good choice.
 
Don; IMHO I believe the 9mm would most likely not overpenetrate. Normally, the higher speed a hollow point is driven too the shallower the penetration and the greater the expansion. Cor-Bon even makes a 90 grain hollow point the screams out of a five inch barrel (1450 fps or higher). Will it under-penetrate? Possibly. But if it does simply pull the trigger again. Best, J. Parker
 
Remember the greater frontal crossection of the 45 will place more of its energy to target thus decreasing penatration.the nine is an overpenatrater with its high speed and small frontal crossection.This would be in FMJ ammo.Before we start talking about the great expansion on some bullets remember that the 45 is preexpanded and will allso expands so invalid argument.
See how much flame I get on this?

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beemerb
We have a criminal jury system which is superior to any in the world;
and its efficiency is only marred by the difficulty of finding twelve men
every day who don't know anything and can't read.
-Mark Twain
 
beemerb; No flame from me. My house gun is a Glock-21 but I live in the country where over-penetration might not be as big a problem. Best, J. Parker
 
If I may be allowed to attempt a summary, it sounds like either will penetrate walls in FMJ, maybe neither with the right hollow point bullet, and hopefully neither with pre-fragmented slugs like Glasers. Is that about right?

Well, I don't care to use FMJ for defense anyway, so it sounds like .45 is not an untoward risk. I realize the incredibly low odds of harming anyone with a stray shot that penetrates the wall, of course, but the gun is there as preparation for an extremely unlikely event in the first place, right?

However, I've been thinking about it and even if penetration isn't a factor, 9mm is still cheaper, easier to place if only by a small margin, and comes in a frame that my wife finds much more comfortable. It's also more common, so I'm going with the CZ-75. Thanks, folks.
 
If you hit the BG, the bullet will probably expand, and if it doesn't stay in the body, it won't have much force after it exits. A JHP won't expand when it hits sheetrock, so it will act pretty much the same as FMJ when it comes to penetrating the sheetrock, and insulation. Either one will probably pass through the walls and still have enough energy to at least wound anyone it hits.
Eric

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Formerly Puddle Pirate.
Teach a kid to shoot.
It annoys the antis.
 
Don:

Bust my chops if it's none of my business but what ever came of that Glock 17 that you won on another forum?

Thanks----WB

PS: I was in the CHI area last week and me and some of my co-workers managed to slip off one day and catch a limit of Coho and King Salmon on Lake Michigan with King Olaf Charters out of Northpoint Marina in Winthrop Harbor, IL.

We bunked every night except one in Wadsworth at Midlane Golf Resort. FWIW, I love IL in the Summer.

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"When guns are outlawed;I will be an outlaw."

[This message has been edited by Will Beararms (edited July 03, 2000).]
 
Don, a couple of points.
1. Read the article on this forum regarding overpenetration.
2. Hollowpoints typically fill up upon impact with wood or sheet rock and perform like a FMJ. They just don't upon up.
3. From a practical standpoint, the 9mm and 45ACP will overpenetrate any apartment or condo wall. Not enough difference to choose one over the other.
4. Plan your defense so your rounds impact your adversary and not the wall. Don't wait for it to happen and then wing it.


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Archie
 
Corbon makes this round called "BeeSafe" It's expensive, but specially designed for home defense. http://www.corbon.com/beesafe.html

This is what you want, this will not penetrate the walls, but WILL kill the bad guy standing in front of you. It's prefragmented...

Albert

PS. Next time you are at an outdoor range, might I suggest bringing two pieces of drywall taped together? That way, you can shoot at it and KNOW if it penetrates to the other side, whatever you are shooting...
 
Check on your walls with the owner or the manager (without stating it's about shooting of course) and ask them if your walls have a fire retention barrier and what it's made of. In many areas a 4" thick concrete wall is required between units for fire protection -- OR two extra layers of thick fire-retardant sheet rock. Obviously if you have a block barrier you will have safer neighbors and of course they may have a gun too...

By the way I tested some Glasers several years ago, the design has not changed, and they penetrated wood and drywall just as well as FMJ. They did however expand quite well in wet stuff like a big ham a side of beef or vegetables.

Regarding .45 and .9mm one of my associates is an avid military historian and he contends that the .9mm Parabellum was designed to penetrate far better than our .45 for urban warfare! He says that most of our G.I.s in WWII picked up .9mm and ammo for shooting when they were involved in the European cities so they could shoot through walls better.

I previously lived in a trailer park -- in a trailer. My solution was to have a short 12 ga. Mossberg pump with HOT trap loads for HD. In my testing the trap load acts like a slug for the first 15 feet as the load stays in the shot cup. If it contacts a wall or piece of meat etc. -- the shot cup is pulled off and the shot rapidly expands. I found that it would penetrate one piece of sheet rock, at up to 15 feet, like a slug and then barely penetrate the second -- with only about the power of a BB gun left to hit the third piece. The sheet rock was placed on both sides of a 2"x4" frame like in a home.

In my tests with .9mm and .45 I found that Quick Shock did a better job as a "safety" round than Glasers and that MagSafe, especially the "police round" was the best.
If you can, find a place to do some testing of your own -- I hope this helped.

Take care.

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Talk is cheap; Free Speech is NOT.

[This message has been edited by Jody Hudson (edited July 03, 2000).]
 
It is true what was posted earlier. Mag safe ammo is NOT designed to break up when hitting something solid like sheetrock or glass, it is designed to fragment in soft tissue or fluid, so in the case where you missed the BG entirely, they are not really that much safer than regular hollowpoints.
For in the home, I like to use .45 silvertips because they have less penetration in both flesh and building materials although a 200 grain corbon isn't bad either.

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"what gives a government that arms the whole world the right to disarm it's own citizens?"
 
I knew this already, but it bears repeating that the most important thing is hitting the target perfectly, so I don't mind that. The way it sounds is that just about anything I trust for self-defense, even from a handgun, will penetrate the walls.

Will, the Glock just never appeared. The FFL Nick used at Buyer's Club America is a liar and a crook. I don't know if they still use him or not, but I hope not. BilltheCat at Glocktalk finally recieved his G30 but my G17 was never sent. Finally, in June, Nick made good by personally sending enough cash by money order to cover the cost of a Glock, telling me to buy it locally and forget the whole thing. But that was when we were graduating and moving out; I still didn't even have a place to live after the wedding when I got the money. It seemed irresponsible to blow such a gift on a gun, so I used it for the bulk of my first month's rent, deposit, etc. Melissa promised that when we had the money to spare again, my new gun would go first on the list. Now we both have jobs and the wedding gifts were very generous, so I'm hoping to have a new pistol soon. Definitely a CZ-75 unless I find a deal I can't refuse on something else. There was a beautiful stainless *&* 645 in the local gunshop used for $450 the other day and I was sorely tempted, but I held out.
Anyway, thanks, guys. I'll look for that article.
 
Don:

I hate it that the G17 did'nt work out but you made a wise decision on the money and I admire you for it. Guns are easy to come by in the scheme of things. A good lady isn't.

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"When guns are outlawed;I will be an outlaw."
 
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