Clearing the Caliber Confusion: .223 Wylde vs. 5.56 NATO

Though they share identical case dimensions, the .223 Remington and 5.56 NATO are slightly different—and the .223 Wylde makes the most of both of these loads.

Brad Fitzpatrick

The 5.56×45 NATO broke cover in 1957 as a military cartridge, and since that time it has served in multiple campaigns and conflicts around the globe. The 5.56×45 offered a lot—it was a flat-shooting, fast cartridge with minimal recoil and minimal weight (read: you can carry a lot of them). So great was the 5.56 that it soon followed in civilian garb as the .223 Remington, a cartridge that has remained viable and popular since its release date.

There are some that will tell you that a .223 and a 5.56 are the same cartridge. Well, in terms of case dimension, that is true. So, how do they differ?

 

Technical Dimensions of the .223 Rem vs. the 5.56 NATO Cartridges

Technical Dimensions of the .223 Rem vs. the 5.56 NATO Cartridges. Image credit: here

The short answer is that they differ with regard to pressure and chamber dimensions. Pressures in the 5.56 cartridge are higher than the .223, and as a result the chamber of the 5.56 is different as well. There’s more throat length in a 5.56 barrel—about .077 inches—and the angle of the throat is different to accommodate increased pressures. It is, therefore, alright to fire a .223 cartridge in a 5.56 chamber, but going the other way can cause pressure problems. Simply put, the .223 doesn’t perform as well in 5.56 chambers as it could. If you have two cartridges that are so similar in external case dimensions why not have one chamber that makes the best of both loads?

Enter Bill Wylde. Bill had the idea to create a chamber that would serve the 5.56 and the .223 Remington equally well. The .223 Wylde has the same chamber angling as the standard 5.56 chamber, so there’s no problem with pressures, and it also has a .2240 freebore diameter. The result? You have a chamber that is sufficient to handle the hotter 5.56 load without concerns about pressure and you get the gilt-edge accuracy that’s common in many quality .223 rifles.

The .223 Wylde Chamber Dimensions

The .223 Wylde Chamber Dimensions

Is there a compelling reason to switch to a Wylde chamber? Well, the most obvious reason is that you can fire .223 ammo without giving up accuracy and 5.56 ammo without worrying about excess pressure. Sure, you can fire .223 ammo all day from a 5.56 without worrying about pressure problems thanks to generous chamber size, but if you really want to tighten those groups that .2240 freebore diameter helps. In fact, .223 Wylde chambers are known for extreme accuracy, which is better on the whole than what you can expect from a standard 5.56×45 chamber.

Better accuracy, more versatility with ammo—so what’s the downside? Well, right now that can be cost and availability. The gains that the .223 Wylde provides haven’t prompted a whole bunch of companies to swap to that chamber, but there are certainly .223 Wylde-chambered target rifles out there. Do you need a Wylde? No, but it will help your long game and will make your AR 15 rifle build even more versatile than it is now.

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Understanding Twist Rate for the 5.56

Matching bullet weight to twist rate is vital for maximum accuracy. How do you know which twist rate is right for you?

Brad Fitzpatrick

 

In the 1960’s, when the 5.56×45 and the accompanying AR platform debuted, both rifles had barrels with twist rates of 1:14 inches, or one full rifling twist for every 14 inches of barrel. That’s because at that time the standard choice in 5.56 ammo was a 55 grain FMJ projectile. And although the 50-55 grain bullet is still a versatile and effect varmint hunting bullet, for military and long-range purposes most ARs have switched to heavier bullets. That means that the AR 15 barrels must switch, too.

Today you won’t find very many 1:14 barrels because, frankly, there isn’t a whole lot of demand for them. They’re good at stabilizing lighter bullets, but they won’t stabilize heavier projectiles. For that reason, the 1:12 is about the slowest AR barrel you’ll see today. Because there’s a “sweet spot” when combining bullet and barrel twist rate, you’ll need to have an idea what type of ammo you’re going to be shooting. If you’re going to limit yourself to 55 grains or less, the 1:12 will work.

 

Originally at 1:14 twist, more common 1:7-1:9 twist rates are available in the market today

But why give up the 5.56/.223’s blessed versatility? Why not get the most out of your rifle?

In that case, you’re probably going to want to look for a faster twist rate that stabilizes larger bullets. 1:10 and 1:9 twist barrels, which work just fine with 55 grain projectiles but will also handle heavier 60, 62, and 69 grain bullets. These two barrel twist rates are situated in the middle of the pack and, generally speaking, allow you to shoot a wider variety of bullets than any slower-twist barrels. But as you go beyond 1:9, barrels do better with heavier bullets and don’t perform as well with lighter ones. Just as slow-twist barrels won’t stabilize heavy bullets properly, fast-twist barrels will sometimes overstablize, which reduces bullet stability and results in poor performance. For that reason, the faster twist barrels—1:8 and 1:7—are best with heavy bullets. 1:8 twist barrels will stabilize bullets up to 80 grains, and 1:7 tubes will actually stabilize heavy, long-for caliber, aerodynamic bullets up to 90 grains.

223_Remington

A small example of the hue variety in bullet profile and weight

So, what’s right for your AR 15? That depends. If I were building a strict varmint gun—something that would almost exclusively fire bullets in the 55 grain and below range—I’d opt for a 1:10 twist rate, which has proven effective for me in the past. The 1:10 is highly versatile and will work with most bullets, from 55 grain polymer tip varmint bullets on up to heavier boat-tails for a little extra reach. If I planned to shoot a bit of every type of ammunition I’d go for a 1:9 or 1:8, which would allow me to take advantage of a broad range of bullets. If I were building a long-range target gun and knew I’d be using bullets from 77 grain on up, well, I’d have a 1:7 twist.

If you’re building a 5.56×45 AR then it will help to know twist rates. You’ll understand how your gun and ammunition work together, and you’ll be able to get the most out of your loads.

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9MM vs .45 Auto and Concealed Carry

The 9MM, The .45 Auto and Concealed Carry:  The FBI Is No Help At All by Brian McCombie

When the Federal Bureau of Investigation (FBI) announced it was returning to 9MM handguns, those who used 9MM’s for their every-day carry firearm acted like the 9MM versus .45 Auto controversy was settled. After all, the FBI–the country’s most respected federal policing agency–had not only selected the 9MM; it had issued a science-heavy explanation of why the 9MM was the best choice over the .45 Auto and the .40 S&W it had been using for a couple decades.

The FBI also stressed that 9MM self-defense rounds had come a long, long way over the last 30 years, and argued the 9MM was actually the equal of the .45 Auto and .40 S&W when it came to “immediate incapacitation.” The 9MM concealed carry crowd jumped on these statements, and proclaimed: the 9MM was the equal of, if not actually better than, the .45 Auto.

The problem with all that? It’s not actually true–not from an ammunition standpoint.

An examination of the FBI’s own report on selecting the 9MM makes it clear the FBI actually choose the 9MM for non-ammunition reasons, including the lower costs associated with running 9MM’s instead of the FBI’s .40 S&W’s–not some huge advantage the 9MM round would provide law enforcement.

The FBI’s report document for choosing the 9MM—widely shared across the Internet—notes that law enforcement officers, “miss between 70 – 80 percent of the shots fired during a shooting incident.” Even on the range, officers aren’t very good shots and handgun recoil—or the inability to adjust to it—was pegged as a big reason for the lack of accuracy.

So if most of your shots are misses, especially in an actual shoot-out, and if handgun recoil makes your shooters even less accurate? The solution, according to the FBI, is the “….9mm Luger [because it] offers higher magazine capacities, less recoil, lower cost (both in ammunition and wear on the weapons) and higher functional reliability rates (in FBI weapons).”

FBI agents had carried 9MM’s in the past. But during the infamous 1986 Miami Florida shoot out with a pair of heavily armed bank robbers, the 9MM’s used by FBI agents fared so poorly, the 9MM round was cited as partially to blame for two FBI agents dead and a third wounded. The FBI went in search of a more powerful round, eventually selecting the .40 S&W.

But how to get around the fact that the .45 Auto uses a larger, heavier bullet that (generally speaking) delivers a larger foot-pounds-of-energy wallop than its 9MM cousin?

The FBI did that by insisting there is no such thing as stopping power. Got that? Stopping power does not exist! According to the FBI document, “Handgun stopping power is simply a myth.”

Ah, the magic of making your own definitions to fit your own argument. The FBI defines “stopping power” as one-shot and an assailant is down and done. In the FBI’s terminology, real stopping power would be “immediate incapacitation,” which is only achieved through a hit to the brain or spine. So, the FBI notes, a hit from a 9MM, .40 S&W or a .45 Auto all have the same effect: bad guy down.

The FBI then indulges in some sleight of hand in discussing the “medical facts” relating to handgun wounds. According to the FBI document, “Due to the elastic nature of most human tissue and the low velocity of handgun projectiles relative to rifle projectiles, it has long been established by medical professionals…that the damage along a wound path visible at autopsy or during surgery cannot be distinguished between the common handgun calibers used in law enforcement.”

It continues, “That is to say an operating room surgeon or Medical Examiner cannot distinguish the difference between wounds caused by .35 to .45 caliber projectiles.”

However. The research cited by the FBI was from 1989 medical studies. These studies examined wounds made from the same relatively ineffective rounds used by the FBI and other agencies in the past.

Not by wounds caused by the more effective self-defense rounds available today.

Today’s 9MM self-defense rounds are better than full-metal jacket and hollow-point rounds used by law enforcement 30 and 40 years ago. But so, too, are their .45 Auto brethren.

Take a look at two current rounds on the market today, Federal’s HST Premium Personal Defense, and Winchester’s Defender line.

9MM Federal HST Premium

9MM Federal HST Premium

According to data supplied by Federal, the 9MM HST round with a 150 grain bullet, and fired from a Glock 43, showed an average diameter expansion to .607”, with 13.7” of penetration, when fired into bare 10% ordnance gelatin. When the gel was covered in heavy clothing, a .597” diameter and 13.25” penetration.

From a standard-sized 1911, the .45 Auto HST firing a 230 grain bullet averaged an expansion to .926” diameter and 12.85” penetration in bare gel, and .831” diameter and 13.35” penetration in heavy clothing.

.45 HST after ballistics testing (Comparison to 9MM)

.45 HST after ballistics testing (Comparison to 9MM)

The same general pattern exists the Winchester Defender loads (data supplied by Winchester): the 45 Auto 230 grain Defender penetrates 12.2” and expands to .84” in bare gel; the 9mm 147 grain Defender penetrates 15.8” and expands to .58”.

Of note: both ammo makers used the standard FBI Protocol for gel testing these rounds.

No one in their right mind wants to get drilled with any of the aforementioned rounds. But the laws of physics suggest very clearly that the heavier bullet, with larger expansion, has to do more damage than the lighter, less expanding bullet.

The FBI would have done a better service to both law enforcement officers and concealed carry holders had they admitted they chose the 9MM despite it offering less knock down than the .45 Auto and the many self-defense loads for it on the market today.

But, they didn’t.

Build your own 9MM or .40CAL polymer pistol here with AWC.

Senator David Vitter M855 Ammo Giveaway

david-vitter-m855-ammo-giveaway

Dinner at the White House? How does that sound? Perhaps enjoying a good meal and conversation with President Obama about the Second Amendment and gun rights? Believe it or not, YOU have a better chance of getting such an invite than the Republican Senior U.S. Senator from Louisiana does. No doubt, the David Vitter M855 Ammo Giveaway saw to that.

Here’s why.

Vitter Giveth What Obama to Taketh Away.

March 11, 2015. The seated U.S. Senator in his second term, now campaigning for Governor of Louisiana, announced the David Vitter M855 Ammo Giveaway. “Obama and his allies are working to restrict our access to guns and ammo, and it is up to us to fight for our rights as gun owners,” said Vitter. “As a show of support for the Second Amendment, I am raffling off a free box of M855 ammo.”

(For your chance to win the David Vitter M855 Ammo Giveaway, go to his official campaign site for Governor of Louisiana. Hurry, it is ending in a couple of days!)

While the Obama-led ATF was recently promoting its proposed ban of M855 5.56 NATO ammo, re-classifying it as “armor-piercing” ammunition, (which is untrue by definition), Mr. Vitter and his Press Secretary, Luke Bolar, cleverly fired back. It was a sign of true marksmanship.

“Senator Vitter had already written a strong letter to the ATF against the ban,” Bolar told AWC. “We were making plans for a scheduled campaign appearance at the Great Southern Gun & Knife Show in Kenner, Louisiana last weekend. We got to talking about the impact on rising ammo prices. So, we decided to buy a box and raffle it off.”

Several hundred law-abiding citizens attending the show signed up in person for The David Vitter M855 Ammo Giveaway. Through his website and social media, the total of entrants now stands around 1,000.

Like you, Mr. Vitter knows winning the raffle isn’t what’s most important. He’s obviously focused on winning an election. The latest polls show he is leading a tight race. But whether or not he becomes the first U.S. Senator in more than 100 years to become Governor of Louisiana, David Vitter has shown he is committed to defending gun rights, and fighting the Obama Administration’s attempted gun grabs and assaults on ammo. His voting record includes:

U.S. Senator David Vitter Voting YES:

Allowing firearms in checked baggage on Amtrak trains.

Co-sponsored bill allowing firearms in National Parks.

Co-sponsored banning gun registration and trigger lock law in Washington D.C.

Applying concealed carry permit to all other states where legal.

 

U.S. Senator David Vitter Voting NO:

Lawsuits vs. gun manufacturers.

Suing gun makers and sellers for gun misuse.

Foreign & UN Aid that restricts US gun ownership.

Banning high-capacity magazines over 10 rounds.

 

(And just for grins, we’ll point out David Vitter was one of only 2 U.S. Senators to vote “Nay” on Hillary Clinton becoming U.S. Secretary of State).

As they say in the bayou, “Whodat?“

Whodat gonna fight to defend the 2nd Amendment and gun rights in Louisiana? AWC knows one loud voice has been and will continue to be… Senator or Governor to be David Vitter.

 

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Former ATF Agent on Ammo Ban M855

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