What is the difference between the 5.45x39 and 5.56mm

[9mmhpfan]

I am wanting to buy a semi auto assult rifle for self defense and have decided to go with an ak format. I have seen ak rifles or conversion kits that chamber 5.56mm m-16 round but have read reports of it not being a very good manstopper in the current conflicts we are in.

I have heard that the russian designed 5.45x39 round is a good manstopper but it is a smaller round than the m-16 round so how can it be a better manstopper than it?

any help you can offer would be appericated

 

[entropy]

It's the bullet disign that makes the 5.45x39 a better stopper. However, not all the 5.45x39 ammo coming into the States has this bullet design. Get an AK in 7.62x39, and you don't have to worry about it, with any bullet design it's an adequate round at SD ranges.

 

[Commissar Gribb]

the silverbear stuff I've been buying is pretty accurate and comes in 60gr.

all in all- it's more expensive but I would take 5.45 over 7.62 for general shooting (for accuracy and recoil).

I've never tested the 5.45 for self defense but it certainly plugs right along with 5.56

 

[rbernie]

What is the difference between the 5.45x39 and 5.56mm

Availability and cost, mostly.

 

[Sleeping Dog]

What is the difference between the 5.45x39 and 5.56mm

.11x6mm

Sorry, couldn't resist.

 

[benEzra]

They're ballistically fairly similar. The 5.56x45mm/.223 Remington was developed first, in the late 1950's, from the old .222 Remington small game hunting cartridge. The Soviets decided that if we were using high-velocity .22's for our military, there must be something to it, so they developed the 5.45x39 for the AK-74, which was phased in in the '70's and '80's to replace the AK-47 (7.62x39mm). Since the 5.45x39 was essentially a copy of our 5.56x45, it's ballistically fairly similar.

Civilian AK-74 lookalikes (5.45mm) are generally regarded as being more accurate, more pleasant to shoot, and easier to shoot well than 7.62x39mm. The ammunition is less common than 7.62x39 but you can get it at gun shows or mailorder from places like Cheaper than Dirt, Sportsman's Guide, and ammoman.com.

On the other side of the coin, the 7.62x39mm is more common, slightly less expensive, and is powerful enough for deer hunting (though just barely) if you're into that, though it's not powerful enough for humane shots on deer beyond 125 yards or so.

 

[beerslurpy]

5.45 seems to fragment far less readily due to thicker jackets. Ballistically they are nearly identical.

 

[Dionysusigma]

So it's...
Germany invents 7.92x33mm.
In response to this, the Russians develop 7.62x39mm (and the Spanish come up with... 7.92x40mm (?) CETME).
Becoming jealous, we invent .223/5.56mm.
The Soviets then invent 5.45x39mm.
Then Belgium comes up with 5.7x28mm.

Then Bubba RedNeck comes up with the .50-.17 Eargenschplittenloudenboomer (.50BMG necked to .17 HMR). :banghead:

 

[Snowdog]

Here's a photo I took a while back.
5.45x39 (center) flanked by 5.56x45 on the left and 7.62x39 on the right.

 

[Commissar Gribb]

5.45x39 reminds me a bit of the x54R cartridge.

 

[Nightcrawler]

5.45 seems to fragment far less readily due to thicker jackets.

Which, on the battlefield, should yeild better penetration of cover. So it's give and take, as always.

I've fired a few rounds through a 5.45mm. Almost like shooting a .22 out of a nearly eight pound AK. Soft as heck.

 

[9mmepiphany]

it has been my experience, though limited due to my location, that the AK platform is usually more reliable in the 5.45x39mm than the 5.56x45mm. this might only apply to early imports. the bullet design of the military issued 5.45x39mm made it a better stopper than the 5.56x45mm

i really like the 5.45mm round better than the 7.62x39mm. it is just more fun

 

[ny32182]

I doubt you could call it a "better stopper"... it is basically very similar in operation to the 5.56. I'd actually prefer the 5.56 ballistics a little over 5.45, but in an AK-74 platform I'd take 5.45 because it is the native chambering.

 

[Commissar Gribb]

I've fired a few rounds through a 5.45mm. Almost like shooting a .22 out of a nearly eight pound AK. Soft as heck.

an astute description.

+1

 

[clange]

If it fragments 5.56 is a far more effective round than 5.45, but the key word is IF. Once you get past the range at which 5.56 fragments, i'd put my money on the 5.45. 5.45 is not designed to fragment, and it doesnt. It tumbles very well, but tumbling is not nearly as effective as fragmentation. There are a couple really good threads about this that you can find in a search if you want more reading.

5.45 is a cool round though, and when fired through a real ak-74 brake there is virtually no muzzle climb, and light recoil. My AKS-74 is my favorite firearm.

 

[Nightcrawler]

5.45 is not designed to fragment, and it doesnt.

Okay, neither was 5.56mm. This is a popular internet myth, that it was designed to fragment. But the US observes the Hague accords, which prohibit fragmentating, expanding, or exploding ammunition.

Proof of this comes from Army tests of that LeMat (RCBD?) fragmention "armor-piercing, limited penetration" oxymoron ammo. They said that the fragmentation effects were contrary to the Hague accords.

5.56mm fragments sometimes becuase of high velocity and a thin jacket. But it's type-classified as ball ammo.

40 grain V-Max is a different story.

Military 5.45mm, on the other hand DOES have an air pocket in the nose to allow the bullet to rapidly tumble when changing media. But just as not all 5.56mm FMJ doesn't fragment, not all 5.45mm FMJ has the air pocket in the nose.

 

[clange]

I didnt say 5.56 was designed to fragment, sorry if it sounded like that. However, when you read about how effective .223/5.56 is, fragmentation is always mentioned, so its not like you can ignore the fact that its effectiveness is tied with fragmentation. Thats all i was getting at.

As far as 5.45, some commerical stuff does have the air pocket, but no steel core (a lot of 7.62x39 does as well actually). I havent seen any tests of commercial ammo though, so i have no idea whether or not it tumbles like the military stuff.

And all of this really only matters if you're bound by the hague accords anyway.

 

[Nightcrawler]

And all of this really only matters if you're bound by the hague accords anyway.

Exactly. There's Hornady TAP if you think fragmentation, tumbling, or other ballistic gymnastics are required.

 

[Father Knows Best]

I've fired a few rounds through a 5.45mm. Almost like shooting a .22 out of a nearly eight pound AK. Soft as heck.

Well, I've never fired a 5.45, but I can't imagine wanting anything softer than my 7.62x39 AK (an Arsenal SA M-7S). Maybe it's because my other rifles are .30's (.30-'06 and 7.62x51), but my AK already seems so gentle that I might as well be shooting .22LR.