The .223 Remington/5.56 NATO
.223 Remington and the 5.56 NATO are very similar rounds though the
actual chamber specifications are slightly different. For all practical
purposes, they are interchangeable. If your rifle has a mil-spec 5.56
NATO chamber it will work just fine with both varieties. If you have a
commercial .223 Remington rifle with a minimum-sized chamber (aka: a
"tight" chamber" then some
5.56 NATO ammo might not fit. That's about it. I don't know of any
reloading dies that do not resize the cases enough to fit either
in the 1950s the USA was firmly convinced that we needed a full-power
cartridge such as the venerable .30-'06 for our military to use. Even
the evidence of the German 7.92 x 33 cartridge used in their StG44
rifle (the first actual assault rifle ever put into use) and the Soviet
7.62 x 39 (M-43) round used in their SKS and AK-47 rifles didn't
convince the "old guard" in the Pentagon. We dug in our heels and
insisted on a .30 calibre (7.62mm) cartridge with power close to the
old .30-'06 whether that made sense or not. So the 7.62 NATO (aka: .308
Winchester) was adopted along with the M-14 rifle in 1957.
War II studies showed that military engagements involving small-arms
fire (that's from rifles, pistols, and submachine guns for the most
part) happened almost always at ranges of less than 300 metres. The
value of having every soldier equipped with a rifle that is effective
out to beyond twice that range was questioned. The Pentagon didn't
listen. Our British and European allies did, but we were the "big dog"
in this fight and our position prevailed -- hence the 7.62 NATO.
in thevery late 1950s or early 1960s (there are different opinions) we got
involved in an internal dispute in Viet Nam. At first we just sent
military advisors who were supposed to stay out of the actual fighting.
That didn't last long, and soon our GIs were firing their M-14 rifles
at the hated "commies." While our GIs were humping their heavy M-14s
and the equally heavy ammo for them out into the boondocks of Viet Nam
a fellow named Gene Stoner at an aircraft company designed a new kind
of rifle. It used a lot of aluminium alloy and plastics to keep the
weight down. The first version was chambered in 7.62 NATO and called
the AR-10. AR stood for Armalite Rifle since it was made by the
Armalite division of Fairchild Aircraft Company. Things never go
smoothly. About this time it became obvious to even the Pentagon that
we needed a lighter rifle for our troops "In Country" as the "grunts" put it.
In many of the Viet Nam jungles you couldn't even see
300 metres distant let alone pick out a target. So the word was passed
to Armalite that the US military might be interested in Stoner's new
rifle, but in a smaller, lighter cartridge. The decision was made to go
with a high-velocity, smallbore bullet similar to those used by varmint
shooters. The .222 Remington was a very popular varmint cartridge, but
it was deemed to be too low-powered for the military's purposes. A
fairly new cartridge called the .222 Remington Magnum looked promising.
It was basically a .222 Remington with a little longer case to hold
more powder. This cartridge was modified a little and became what we
now know as the .223 Remington. This pretty much doomed the .222
Remington Magnum to oblivion. The military adopted it as the 5.56 NATO.
The Armalite rifle was redesigned to fit the smaller round, and renamed
the AR-15. Since this first "AR-15" was intended for military use it
was a selective-fire weapon,
meaning that it had the ability to shoot like a machine gun. The AR-15s
that you see for sale in your local gun store are a later design and
don't have that selective fire function.
was a huge amount of resistance to using a "puny .22" and a "plastic"
rifle by the military brass and by many gun writers. Eventually a bunch
of AR-15s were bought by the US Air Force to be used mainly guarding
flight lines. The little rifle quickly caught on. It was adopted as the
US Rifle, M-16 along with its cartridge, the .223 Remington or 5.56
NATO. Yes there were some very trying teething problems in the early
years, but the little cartridge did the job and is still one of the
most popular in the US if not the world.
Many states do not
allow hunting deer-sized game with the .223 but others do. It is
clearly right on the edge of the envelope as far as being powerful
enough for that use. There are other similar but different cartridges
that are a better choice for medium-game hunting.
The .223 /
5.56 in an AR type rifle or carbine is a very good choice for home
defense. Before you even bring up the bugbear of "overpenetration"
let's make two things clear. First, any cartridge that will stop a
determined attacker/intruder will go through the wall of a modern
house. That's just the way it is. No projectile in existence will go
through 8 to 10 inches (or more) of meat and bone, but not go through a
couple of layers of drywall. It just doesn't work that way. Second, the
lighter-weight bullets (55 grains or less) -- especially those of the
hollow-point variety -- fired out of the .223 / 5.56 weapons have
actually been tested and proven to penetrate less
through walls and other common barriers than almost all full-power
handgun loads and less than buckshot fired from a shotgun. It's all
about the inertia of the projectile which is directly related to the
mass of that projectile. It has been tested and proven. Believe it or
Almost any cartridge adopted by our military is certain to
become popular amongst American shooters, right or wrong. The .223 /
5.56 is no exception. It is also easy to shoot well as it has much less
recoil than many other centrefire rifle cartridges. It is plentiful (at
least most of the time) and inexpensive (again, most of the time) which
lends itself to more practicing -- always a good thing. As I get older
some of my bigger rounds hammer a bit too hard on my shoulder to be
pleasant to shoot for very long, but the .223 / 5.56 does not have that
problem -- at least not yet.