The Down Range Forum
Member Section => Down Range Cafe => Topic started by: TexGun on March 02, 2008, 03:16:16 PM
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Alright folks, I need the low-down on 5.56 NATO vs. .223. Are they truly interchangeable? When I buy my AR which cal do I buy? ???
-TexGun (utility rifle newby)
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5.56 is loaded to a higher capacity than the .223. If your barrel was made for the .223, do not shoot 5.56. If your barrel was made for the 5.56, you can shoot both.
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Any issues that you are aware of with the action clycling using .223 in a 5.56 AR?
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.223 cycles fine in my 5.56 AR.
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.223 cycles fine in my 5.56 AR.
Same here. No problems with either.
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My DPMS eats .223 like sunflower seeds - It takes everything you put in its mouth, spits out the waste, and keeps asking for more. I bought the 5.56 based on it being a heavier action, and it has never failed on anything I've run through it.
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Same here. No problems with either.
Best web page I've ever seen on 5.56 ammo:
http://www.ammo-oracle.com/
Includes short answer(s) on differences on .223 & 5.56.
Enjoy.
Ken
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Similar but not the same…
5.56mm v. 223 Remington
Deconfusing the issues of a couple of differences…
Summer 2007 Advisory: With the increased demands for ammunition… check ammo prices (and availability) lately?… by the U.S. Military and the multi-national "war on terrorism," the regular suppliers of small arms munitions have gone to maximum capacity (double and triple work shifts, etc.) and new resources have been brought on-line. In some instances, Quality Control and Quality Assuance (QC/QA) has suffered, and the issue of 5.56mm v. 223 Remington has taken on a greater significance.
Not to unduly alarm anyone, but as always, "ya pays your money and takes your chances."Almost a quarter of a century ago, SAAMI recognized potential problems with shooters assuming that the 5.56mm cartridge was identical to the commercially available .223 Remington round. Here is their 31 January 1979 release, with some minor errors corrected:
With the appearance of full metal jacket military 5.56 ammunition on the commercial Market, it has come to the attention of the Sporting Arms and Ammunition Manufacturers' Institute (SAAMI) that the use of military 5.56mm ammunition in sporting rifles chambered for Caliber .223 Remington cartridges can lead to higher-than-normal chamber pressures and possible hazards for the firearm, its user and bystanders.
Tests have confirmed that chamber pressures in a sporting rifle may be significantly higher in the same gun when using military 5.56mm ammunition rather than commercially loaded Caliber .223 Remington cartridges, according to SAAMI.
SAAMI points out that chambers for military rifles have a different throat configuration than chambers for sporting firearms which, together with the full metal jacket of the military projectile, may account for the higher pressures which result when military ammunition is fired in a sporting chamber.
SAAMI recommends that a firearm be fired only with the cartridge for which it is specifically chambered by the manufacturer.
In Rifle Chambered For Do Not Use These Cartridges
223 Remington 5.56mm Military
222 Remington
30 Carbine
Additionally, SAAMI's Unsafe Arms and Ammunition Combinations Technical Data Sheet page states:
The .223 Remington is rated for a maximum of 50,000 CUP while the 5.56mm is rated for 60,000 CUP. That extra 10,000 CUP is likely sufficient to cause a failure in a chamber that's only rated for the "sporting" .223 Remington.
The .223 Remington and the 5.56mm NATO, when checked with a chamber ream from a reliable manufacturer of each, also have discernable differences in the areas of freebore diameter, freebore length (leade) and angle of the throat.
SAAMI
Technical Office:
P.O. Box 338
Branford
CT 06405-0338(Ironically, given the nature of the on-line confusion exhibited by .30 caliber shooters, no similar SAAMI advisory is given concerning 7.62 NATO beyond the fact that those who have rifles chambered in "308 Winchester" shouldn't attempt to shoot cartridges marked "7.62x39" or "300 Savage." Well, duh!)
However, the estimable Clint McKee of Fulton Armory, has thoughtfully provided a brief monograph, The difference between 5.56mm and .223 Remington chambers in the AR-15®-type rifle, which explains this issue in greater (but quite readable) detail.
Olin's Winchester Ammunition site, in 2001, addressed this matter as well, in a concise monograph by Paul Nowak, and Randall Rausch has a number of excellent technical documents, with graphics displaying the differences between the two cartridges, available at AR15barrels.com. Of particular interest are headspace and reamer dimensions.
Further Views on "Differences"
At the October 2001 IALEFI Conference in Reno, Nevada, Giles Stock, retired from Phoenix Police Department after 20 years service, discussed the differences between the .223 Remington/SAAMI and 5.56mm/NATO rifle chambers. The long-time range master for handgun, rifle, carbine and shotgun at Gunsite and developer of the acclaimed Giles Tactical Sling suggested that, as a general rule, recreational rifles have the former, and military rifles the latter… but there is some overlap, most notably in the popular Sturm Ruger Mini-14 which has been offered in both specifications!
NATO chambers have a long leade1. SAAMI chambers are tighter and have a short leade. SAAMI chambers are designed for increased accuracy, but will yield dangerously high pressures in guns using military ammunition and/or which are subject to high volume shooting. Under such high pressures, a primer may back out completely, drop into the action and cause the firearm to stop working.
It has been suggested that an autoloading rifle utilizing a SAAMI-spec chamber may increase risk of overpressure due to the tighter, shorter leade which retards the projectile somewhat as it is attempting to exit the case. Leave the SAMMI chambers to the a bolt action and single-shot rifles.
ArmaLite, not the original, but the Eagle Arms pretenders, has its own views on the subject.
Winchester "White Box" Confusion
This has been making American shooters nuts for a number of years now… particularly in the immediate aftermath of 11 September 2001 when there was a major run on 5.56mm ammunition. Winchester's "generic" or "budget" USA, or "white box," brand of ammunition actually has two different 55-grain FMJ rounds, and one has to look closely at the "small print" to discern the difference.
For openers, in addition to the ATK-operated Lake City plant2, Winchester is also a primary supplier of M193 to the U.S. military. That particular X223R1 round is commercially available in the white USA box product encoded "Q3131." What few realize is that Israeli Military Industries (IMI), the sole supplier of ammo to the Israeli Defense Force (IDF), also supplies their M193 as a subcontractor for Winchester; that round is often made available in the USA white boxes marked "Q3131A." By most reports, qualitatively, it is the same round and performs virtually the same as the home-grown variant.
1.- Leade is the distance the projectile of a chambered round must travel upon ignition before it enters the bore of a barrel. It is measured in thousandths of an inch, and is a datum of considerable interest to benchrest shooters.
2.- The government-owned, contractor-operated Lake City Army Ammunition Plant (LCAAP) in Independence, Missouri, is the largest (458 buildings on 3,935 acres) small-arms manufacturing plant in the world.
Founded in 1941, "Lake City" manufactures and proof-tests small arms (5.56mm - 20mm) munitions. It was initially operated by Remington Arms Company until 1985 when Olin Corporation bid and was awarded the contract to operate the facility. In 1999, Alliant TechSystems (ATK) in conjunction with Federal Cartridge Corporation won a ten-year contract to assume the operations. ATK subsequently acquired Federal Cartridge from Blount Sporting Goods Division.
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Just to throw a curve ball into the mix, there's also the .223 Wylde. It's a combination of 5.56 and .223 Remington dimensions, allowing safe NATO-spec cartridge use but designed to give improved accuracy with commercial-spec ammo. I believe the main difference is a slightly long throat compared to the 5.56x54mm specification. Think of it as a best of both worlds situation. A lot of the Rock River models come in .223 Wylde.
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your right justbill, the main reason for the difference was the chamber a little larger for automatic fire, using some of the escaping gas to help in the ejection process, where the 223 is tight to give better long distance accuracy. The wylde is an either or chamber. I prefer the 5.56 chamber in 1 in 9 twist. Twist is important also ;D
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I'm in complete agreement. My RRA Entry Tactical is also chambered for 5.56mm. I just wish I had the option for a slower than 1-in-9" twist from the manufacturer.
(http://www.hunt101.com/data/500/thumbs/33860RRA_ET.jpg)
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Mine is 1/7 twist.
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Its a good think I'm on this forum, because just when I think I've got a handle on this issue. I begin to relize I really don't know squat about choosing a caliber/proper rate of twist for the AR I want. Keep up the info, its much appreciate.
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Well, i guess that clears it up for me. Guess i'm going for 5.56 so I can run either.
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Its a good think I'm on this forum, because just when I think I've got a handle on this issue. I begin to relize I really don't know squat about choosing a caliber/proper rate of twist for the AR I want. Keep up the info, its much appreciate.
As a rule of thumb and assuming 5.56 NATO/.223 Remington, a 1-in-9" twist will be fine if the majority of loads you use are 62-grains or less. If you want to go heavier in bullet weight, you'll want a slower twist like Don's 1-in-7" barrel. This is also the same twist used in the current generation of M16's and M4's. (The military first went to 1-in-7 to stabilize the tracer cartridge using a rather long bullet. It also works great for the 75- and 77-grain BTHP loads that exhibit excellent long-range accuracy. Specialized military troops using these loads in Afghanistan and Iraq also report enhanced lethality compared to standard M855 Ball.)
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My RRA has a 1 in 8 twist. They make them in several flavors. If you want a slower twist just tell them when you place the order.
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When I purchased my M4gery they only offered 1-in-9. You can now get a 1-in-7 with the carbines, 1-in-8 Wylde-chambered barrels in rifles.
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Based on all of this good feedback and the way the way my fellow Texans are turning out for the democrats, i'm placing my order tomorrow!!!
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That's not a bad idea at all. I foresee some truly dark days ahead as gun owners if either Clinton or Obama is elected. (Not that McCain is a 2nd Amendment stalwart but he'd certainly be the runaway favorite solely based on gun issues.) Funds don't allow me to purchase another fully assembled AR right now but I will be getting a stripped lower receiver or two as a "just in case" hedge against any early attempts to ban EBR's.
BTW, may I ask which specific AR models you're considering?
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I'm really not sure right now. Based on some feedback from some other friends I'm leaning towards a Busmaster or S&W(Stag). Any advice on specific models? My big requirements are, adjustable stock and removeable carry handle. I'm a little old school, so I'm not really looking at any with the carbon fiber receivers.
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Ive seen them new for as little as 700.00 (olympic) you can always add some goodies. IMO they are all cookie cutter rifles much like 1911s just some have a better name and truly some are built with better materials.
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I'm really not sure right now. Based on some feedback from some other friends I'm leaning towards a Busmaster or S&W(Stag). Any advice on specific models? My big requirements are, adjustable stock and removeable carry handle. I'm a little old school, so I'm not really looking at any with the carbon fiber receivers.
I think you're on the right track in desiring an adjustable stock and avoiding the carbon fiber guns. Bushies and Stags are good guns. I chose Rock River Arms because they won the large contracts for both DEA and FBI. I figured both of those agencies know a thing or two about what makes a reliable fighting carbine. I settled on the Entry Tactical, which can be seen here.
http://www.rockriverarms.com/index.cfm?fuseaction=category.display&category_id=217 (http://www.rockriverarms.com/index.cfm?fuseaction=category.display&category_id=217)
An unforeseen plus in favor of the RRA is their two-stage trigger. I didn't realize how much a difference it would be until compared side-by-side with a couple of other AR's with conventional triggers owned by a friend. He was equally impressed, saying the RRA trigger was very comparable to the expensive Jewel unit installed in his match AR. He was so impressed in fact that his next AR was a RRA after years as happy owner of several black rifles from another manufacturer.
I strongly recommend sticking with a chrome lined barrel. I'd opt for the lightweight 1-in-7" configuration.
My Entry Tactical was ordered with the detachable A2 carry handle but I quickly switched to a folding BUIS/EOTech holosight combination. To be honest, if I ordered another AR today I'd opt for no handle at all. IMO a carry handle is quite limiting.
Whichever AR you settle upon, I suggest getting a good sling mounted as soon as possible. It really makes a big impact on any gun handling beyond slow fire off a bench. I chose a Marom Dolphin Sayeret sling from Israel, seen here.
http://www.zahal.org/rifle/p26.htm (http://www.zahal.org/rifle/p26.htm)
It's issue for the IDF. Mine is top-mounted like the Israelis do, which allows a lot of versatility in carry options. I purchased mine from DSG Arms in Fort Worth.
Stock-up on good magazines. I've had excellent service from AR Stoner 20- and 30-rounders from MidwayUSA. These are actually C-Products mags with a proprietary MidwayUSA floor plate stamping. Great reliability at an affordable price. My friend mentioned above has also had good results with Magpul PMAG's and Brownell's.
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Alright boys and girls... Just returned from vacation(in Mr. Bane's home state) and bit the bullet. Bought a DPMS!!!! Can't wait to head for the farm this weekend to site it in!!!
I'm also placing an order with Midway later this week that will include some extra mags. Don't want to get caught in front of a new administration with my pants down!!!
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Which model did you settle upon?
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Lite 16 with A3 upper. Shot it today!
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I prefer the A1 sights as found on your Lite 16 to the A2 rear most often found on most carry handle AR's. IMO they're less apt to be knocked-off zero by accident. Who cares if you need an adjustment tool? Once you're zeroed at the range you've got virtually no worries short of catastrophic damage that would render the carbine inoperable regardless of sights.
The Lite 16 is very comparable to the GUU-5's used by many USAF personnel, including Pararescuemen and Combat Controllers. Works for them.
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I prefer the A1 sights as found on your Lite 16 to the A2 rear most often found on most carry handle AR's. IMO they're less apt to be knocked-off zero by accident. Who cares if you need an adjustment tool? Once you're zeroed at the range you've got virtually no worries short of catastrophic damage that would render the carbine inoperable regardless of sights.
The Lite 16 is very comparable to the GUU-5's used by many USAF personnel, including Pararescuemen and Combat Controllers. Works for them.
Yes but they are often to busy doing their jobs to worry about shooting, They usually have grunts with them for that, Their weapons are generaly for personal protection. Now that I think about it that may validate your point.
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Think Takur Gar (aka The Battle of Roberts Ridge), among others.
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The dealer had an aftermarket rear flip up sight already on the AR. It is a PADS sight. I've never heard of this brand and have only found one online store that sells it. (see link) But, It worked well for me yesterday.
Seen one?
http://www.m-16parts.com/index1.html
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The dealer had an aftermarket rear flip up sight already on the AR. It is a PADS sight. I've never heard of this brand and have only found one online store that sells it. (see link) But, It worked well for me yesterday.
Seen one?
http://www.m-16parts.com/index1.html
Looks like a Matech to me, which as you can see below is the BUIS on my RRA carbine. I've never heard of it being referred to as a PADS.
(http://www.hunt101.com/data/500/thumbs/33860RRA_ET.jpg)
I like the sight a lot.
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Okay, why the thumbnail sized image? I linked to a copy ~ 800 x600.
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Looks like a Matech to me, which as you can see below is the BUIS on my RRA carbine. I've never heard of it being referred to as a PADS.
(http://www.hunt101.com/data/500/thumbs/33860RRA_ET.jpg)
I like the sight a lot.
It's an acronym, like ACOG, but I forget what it stands for
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Figured it might be an acronym. There's no markings on it other than the elevation and windage marks. However, i haven't taken it off yet to check the bottom of the base..
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Ok, I think I've got the image problem figured out. Here's my RRA again, showing the deployed Matech.
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Ok so, I saw a .223/5.56x45 Ingram??? Is this round ok to be fired through a .223 chambered rifle??? I plan on getting a Vector arms V93 and it is specific to the .223.
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Is this round ok to be fired through a .223 chambered rifle?
Nope, I don't believe it is. Isn't the Ingram one of those many wildcats along the lines of the Ackley Improved variations? If I'm correct, it has a shallower shoulder fire formed in a special Ingram chamber. You can shoot standard .223's in an Ingram chamber but probably not the reverse.