5.56 mm NATO versus .223 Remington
- Thread starter metoe
- Start date
5.56NATO is just the military designation for the spec. .223 Rem is the commercial name. Otherwise, they're interchangeable.
Marstar wants $125 for 400 rounds of Winchester 55 grain FMJ. Sold out though. They want $239.99 for 200 rounds of "tin core" 5.56.
Shooter's Choice, in Waterloo, Ontario wants $21.95 for Remington factory SP's.
You shouldn't have any trouble finding .223 in Crappy Tire or any local gun shop. If you already have the restricted AR that you likely won't get an ATT for to shoot it, you'll have to try a box of as many brands of ammo as you can to find the ammo your rifle will shoot well.
If you don't have the rifle you'll need a Restricted PAL first.
Marstar wants $125 for 400 rounds of Winchester 55 grain FMJ. Sold out though. They want $239.99 for 200 rounds of "tin core" 5.56.
Shooter's Choice, in Waterloo, Ontario wants $21.95 for Remington factory SP's.
You shouldn't have any trouble finding .223 in Crappy Tire or any local gun shop. If you already have the restricted AR that you likely won't get an ATT for to shoot it, you'll have to try a box of as many brands of ammo as you can to find the ammo your rifle will shoot well.
If you don't have the rifle you'll need a Restricted PAL first.
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- Location
- Southern ON.
Not really...
Shooting .223 in a 5.56 chamber/barrel is fine but if you shoot 5.56 in a .223 chamber you'll be in for a surprise.
Stolen from Ammo Oracle-
Q. What is the difference between 5.56×45mm and .223 Remington ammo?
In the 1950's, the US military adopted the metric system of measurement and uses metric measurements to describe ammo. However, the US commercial ammo market typically used the English "caliber" measurements when describing ammo. "Caliber" is a shorthand way of saying "hundredths (or thousandths) of an inch." For example, a fifty caliber projectile is approximately fifty one-hundredths (.50) of an inch and a 357 caliber projectile is approximately three-hundred and fifty-seven thousandths (.357) of an inch. Dimensionally, 5.56 and .223 ammo are identical, though military 5.56 ammo is typically loaded to higher pressures and velocities than commercial ammo and may, in guns with extremely tight "match" .223 chambers, be unsafe to fire.
The chambers for .223 and 5.56 weapons are not the same either. Though the AR15 design provides an extremely strong action, high pressure signs on the brass and primers, extraction failures and cycling problems may be seen when firing hot 5.56 ammo in .223-chambered rifles. Military M16s and AR15s from Colt, Bushmaster, FN, DPMS, and some others, have the M16-spec chamber and should have no trouble firing hot 5.56 ammunition.
Military M16s have slightly more headspace and have a longer throat area, compared to the SAAMI .223 chamber spec, which was originally designed for bolt-action rifles. Commercial SAAMI-specification .223 chambers have a much shorter throat or leade and less freebore than the military chamber. Shooting 5.56 Mil-Spec ammo in a SAAMI-specification chamber can increase pressure dramatically, up to an additional 15,000 psi or more.
The military chamber is often referred to as a "5.56 NATO" chamber, as that is what is usually stamped on military barrels. Some commercial AR manufacturers use the tighter ".223" (i.e., SAAMI-spec and often labeled ".223" or ".223 Remington") chamber, which provides for increased accuracy but, in self-loading rifles, less cycling reliability, especially with hot-loaded military ammo. A few AR manufacturers use an in-between chamber spec, such as the Wylde chamber. Many mis-mark their barrels too, which further complicates things. You can generally tell what sort of chamber you are dealing with by the markings, if any, on the barrel, but always check with the manufacturer to be sure.
Opinion: In general it is a bad idea to attempt to fire 5.56 rounds (e.g., M193, M855) in .223 chambers, particularly with older rifles.
Fact: SAAMI specifically warns against the use of 5.56mm ammo in .223 chambers. The .223 SAAMI specification was originally made with bolt rifles in mind.
The (ever so slight) difference in chamber dimensions between 5.56 and .223 have SFA to do with the ammo. While you may encounter Nato spec ammo that is a little hot, something chambered in .223 will likely fire it fine.
There is no difference in the dimensions of the rounds!!
There is no difference in the dimensions of the rounds!!
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Throttle_monkey1
CGN Ultra frequent flyer
I have both 5.56 and .223 ammo. I found the m193 I have to have slightly more "oomph" when I pull the trigger. slight but noticeable
All my .224/5.56 guns have 5.56 barrels, so i shoot both .223 and 5.56 through them. I wouldn't shoot 5.56 through a .223 chamber
All my .224/5.56 guns have 5.56 barrels, so i shoot both .223 and 5.56 through them. I wouldn't shoot 5.56 through a .223 chamber
Quote:
Some commercial AR manufacturers use the tighter ".223" (i.e., SAAMI-spec and often labeled ".223" or ".223 Remington") chamber, which provides for increased accuracy but, in self-loading rifles, less cycling reliability, especially with hot-loaded military ammo. A few AR manufacturers use an in-between chamber spec, such as the Wylde chamber. Many mis-mark their barrels too, which further complicates things. You can generally tell what sort of chamber you are dealing with by the markings, if any, on the barrel, but always check with the manufacturer to be sure.
Sorry Scotty, I'm new to the AR15 platform... and sometimes slow even on my fastest days. I've narrowed my choices down to Armalite & LMT, are both of these 5.56 or are they a .223 version. I've assumed they are 5.56 from all the info I've been able to read so far. Just want to make sure I make the right decision the first time around.
Thanks for any info provided to a noob.
Some commercial AR manufacturers use the tighter ".223" (i.e., SAAMI-spec and often labeled ".223" or ".223 Remington") chamber, which provides for increased accuracy but, in self-loading rifles, less cycling reliability, especially with hot-loaded military ammo. A few AR manufacturers use an in-between chamber spec, such as the Wylde chamber. Many mis-mark their barrels too, which further complicates things. You can generally tell what sort of chamber you are dealing with by the markings, if any, on the barrel, but always check with the manufacturer to be sure.
Sorry Scotty, I'm new to the AR15 platform... and sometimes slow even on my fastest days. I've narrowed my choices down to Armalite & LMT, are both of these 5.56 or are they a .223 version. I've assumed they are 5.56 from all the info I've been able to read so far. Just want to make sure I make the right decision the first time around.
Thanks for any info provided to a noob.
Tommy, If you've narrowed it down to Armalite and LMT as your final choices here's my $0.02. They are both available with the 5.56 chamber but take a look at the barrels. Armalite is generally a 1 in 9 and LMT goes with 1 in 7. If you see yourself using the heavier bullet weights the consensus here is go with the 1 in 7, why limit yourself from the start. I went LMT and couldn't be happier. Drop Mark at Questar a line, great guy to deal with.
Do a quick search, there are a few good threads for first time AR buyers with recommendations from experienced users and professionals.
I have a Armalite 1/9 chrome lined mid length upper which is great. T-marked upper, BCG is done properly and the feed ramps were great. For $747 with CH and BCG and $850 for a 14.5 carbine I will keep the change over a LMT upper.
I can shoot 69SMK's fine out the barrel but these days all it gets is 55Gr FMJ at the range.
- Location
- Pile of Bones, SK
Can this be stickied already???
What would be really nice...and I've seen similar mentioned here somewhere....it a complete thread for "everything AR15" for complete noobs like myself. It may cut down on the redundant questions and save some "search" time too.
I've yet to see a SINGLE occurance of a rifle being destroyed, or heavily damaged, but switching those two interchangeable cartridges ... The difference in chamber dimensions can easily be attributed tot he military allowing for mud and dirt to make sure their guns WORK. Mind you I'm talking about factory rounds, who knows what people put in reloads these days ...
I was looking at my colt sporter a2 hbar the other day and on the side of the receiver is .223 yet on the hbar it has 5.56 and the twist rate on it. Does this mean i could use 5.56 or .223 because i don't want to use it if it is a .223 ?
