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View Full Version : Heavy Barrel or not? Diff btw 5.56 and .223


Jicko
12-23-2005, 12:27 PM
What is a heavy barrel? Is it a good thing?

DPMS called theirs "heavy barrel"? Are Stag upper halves "heavy barrel"?

I am looking at Stag's 1H upper halves, and it seems to have everything I wanted (flat-top w/ detachable handle, 5.56, 16" chrome lined 1:9, A2 flash hider $545).... any comment or review? How's Stag's quality?

Also, what's the diff between 5.56 and .223? Some people tends to use them interchangeably.... but I have also heard that .223 can be used in a 5.56, but no the other way round? Myth, Rumor, Truth or Err?

Stanze
12-23-2005, 12:33 PM
Heavy barrels are thicker and heavier than non-heavy barrels. IMO, they make the carbine heavier than it needs to be, and make it front heavy.

I heard good things about Stag.

the .223 vs. 5.56mm issue is heavily discussed, there are good sites that break it down, detail by detail. Can someone post a few?

~Scott~
12-23-2005, 12:34 PM
From what I understand, 5.56 is Mil-Spec and is manufactured under a different set of protocols... SAAMI vs ?

Anyway, 5.56 may end up being a bit "hotter" than the .223 which I believe is why many manufacturers specifically state not to use 5.56 in their rifles....

I think....:rolleyes: :D

sintax
12-23-2005, 12:36 PM
It all kinda boils down to what type of gun you are trying to build. You may want to go with more of a govt profile if you plan on carrying it around.

Stags uppers are very nice quality.

As for 5.56 and .223.... 5.56 is the nato standard, usually you see .223 in match barrels.

Try searching on AR15.com there is a wealth of knowledge over there and it will save us from getting innodated with all of these very monotonous ar15 config questions.

Anonymous Coward
12-23-2005, 12:37 PM
Read the next couple of sections following this link:

http://www.ammo-oracle.com/body.htm#diff

MicronuT
12-23-2005, 12:41 PM
quoted from the oracle..

Q. What is the difference between 5.5645mm 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.

Typical Colt Mil-Spec-type markings: C MP 5.56 NATO 1/7

Typical Bushmaster markings: B MP 5.56 NATO 1/9 HBAR

DPMS marks their barrels ".223", though they actually have 5.56 chambers.

Olympic Arms marks their barrels with "556", with some additionally marked "SS" or "SUM." This marking is used on all barrels, even older barrels that used .223 chambers and current target models that also use .223 chambers. Non-target barrels made since 2001 should have 5.56 chambers.

Armalite typically doesn't mark their barrels. A2 and A4 models had .223 chambers until mid-2001, and have used 5.56 chambers since. The (t) models use .223 match chambers.

Rock River Arms uses the Wylde chamber specs on most rifles, and does not mark their barrels.

Most other AR manufacturers' barrels are unmarked, and chamber dimensions are unknown



Q. Which should I be looking for in an AR15, a 5.56 NATO or .223 Remington chamber?

This is really a matter of the role for which you plan to use your AR. .223 Remington chambers will give you slightly better accuracy, which is important for a match or varmint rifle. Any loss of feeding and cycling reliability and the restriction against shooting military ammo isn't as important as the accuracy gains for a rifle used in these roles, because for these rifles, accuracy is everything. People who just want to plink or who plan to shoot military ammo (such as most of the cheap surplus ammo available), and especially those who may use their AR as a weapon, should choose 5.56 chambers.

Mike Searson
12-23-2005, 12:42 PM
Originally, when the AR15/M16 platforms debuted the barrels were lightweight and pencil thin.

When the M16A2 version debuted in the mid1980's, the Marine corps specifically asked for a heavier bbl forward of the handguards. Although the heavy barrel helped stabalize the flight of the bullets, the primary reason was to keep the barrel from bending...as a significant number of Marines, Soldiers, etc were using the front end of the barrel as a probe or prybar (mostly the former).

Civilian manufacturers followed suit and Colt offered the HBAR as a variant with a heavy barrel all the way to the chamber. This was better for the civilian shooter as most civilian uses of this rifle do not include carrying the damn thing on 30 mile forced marches. The unloaded weight of an M16A2 was 7.9 lbs, the Colt HBAR was 9.5 lbs if I recall correctly.

I prefer heavier barrels on my rifles. As the bullet travels down the barrel, the recoil creates harmonic vibrations. Think of your barrel as a giant tuning fork. The heavier barrel minimizes these vibrations and aids in barrel cooling as the heat generated is spread over a greater surface area.

Hope this helps.

Jicko
12-23-2005, 12:44 PM
I do try to read up on ar15.com before asking over here. But then, as there are wealth of info over there, it is really TOO MUCH info.....

For example, when I ask this 5.56 vs .223 question, all I want to know is, can I get the Stag 5.56 and that will work for both 5.56 and .223... ie. a general purpose rifle... (and I got my simple answers here on this board, and I bet a lot of us, who are AR-newbies, would appreciate the short and quick answer that most of us have in our heads now)

I rather leave the long, and technical debate over on ar15.com... and short quick and simple questions here.

BigAL
12-23-2005, 1:03 PM
What is a heavy barrel? Is it a good thing?

DPMS called theirs "heavy barrel"? Are Stag upper halves "heavy barrel"?

I am looking at Stag's 1H upper halves, and it seems to have everything I wanted (flat-top w/ detachable handle, 5.56, 16" chrome lined 1:9, A2 flash hider $545).... any comment or review? How's Stag's quality?


Since they have answered the .223/5.56 stuff I'll try to addresss this. Heavy barrels are typically much thicker under the handguards than the part you see after the front sight. I think makers try to push them as they require less time on the lathe being turned down and are therefore cheaper to produce. The military's M-16 do not use heavy profiles. They have their own government profile where the barrel is skinnier under the handguards and then gets thicker from the front sight to the muzzle. Then there is the M4 profile which is similar to gov't profile but there is a cut out in between the front sight and the muzzle where the barrel breifly tapers. This is there to mount the M203 grenade launcher and is more or less useless to us. The Stag 1H has this M4 profile. So no, the Stag 1H is not heavy barreled. Now, the standard M4 barrel length is 14.5" but the Stag 1H is 16" for legal reasons. You can get a 14.5" barrel but it has to have a permanently attached muzzle device that brings it past 16". I generally despised heavy barrels. I see them as un-needed weight on a rifle that is designed to be carried a lot. It also puts this weight where you don't want it on the muzzle end and tends to unbalance the rifle. Sure a heavy barrel on a machinegun makes a lot of sense but no full auto for you so it's a moot point. The only exception I would make is if I was building some uber accurate match gun or never intended to take the barrel off the bench.

Stag(aka CMT) quality is excellent and represents a great value. The other subtle thing I like about the 1H Stag uppers is they have a side front sling, which is better for mounting a 3 point tac sling. Most makers come with a standard bottom sling mount. CMT actually is a major subcontractor for the big AR makers. I'd take Stag over DPMS everyday of the week. Finally, Stag also made a limited number of 1/7" uppers with a 14.5" barrel and perm attached FS making it civi legal. They are more expensive than the standard package but give you the ability to shoot the heavy 75+ grain bullets that are both more accurate and offer improved terminal balistics over lighter stuff. The ammo oracle covers all this in depth.

And last, if you are going to buy I STRONGLY suggest you get it from Grant at
http://gandrtactical.com/cmt.htm. He is a standup guy, has good prices, and ships fast.

PIRATE14
12-23-2005, 1:08 PM
Stag are the best bang for the buck today.
1/9 chrome lined, shaw barrel (light under HG)
side sling adapter
5.56 NATO
fatter M4 handgaurds, not as nice as colts but not as cheesy as BM

upgrades on one model
MP bolts
M4 recievers
M4 barrel ext

lifetime warranty

Most of my rifles are all COLT but gotta a few of the other ABR
and now STAG

Go w/ a 5.56 chamber unless u r going to shoot matches,
if so look at 223 Wylde or 223
Noveski is making a 5.56 Nato match but I haven't checked those out yet

My rifles are either really heavy or really light
some are designed for accuracy
some are desgned for easy carry and reliability
I've got a few SS midlength that aren't too much heavier than a RRA tactical entry and those shoot .55-.75 groups

czp01
12-24-2005, 12:44 PM
I am looking at Stag's 1H upper halves, and it seems to have everything I wanted (flat-top w/ detachable handle, 5.56, 16" chrome lined 1:9, A2 flash hider $545)....

I also want the Stag/CMT 1H upper. I found a couple places that are cheaper than the price you have. One place is offering $525 shipped, and $485 shipped if you replace the Stag/CMT carry handle with a DPMS handle. Let me know if you're interested.

PIRATE14
12-24-2005, 1:25 PM
There Are Two Types Of Carry Handle
Make Sure You Get The One That Is For F Marked
Front Site Base
Don't Get Fooled By A Cheaper Price

czp01
12-24-2005, 1:45 PM
There Are Two Types Of Carry Handle
Make Sure You Get The One That Is For F Marked
Front Site Base
Don't Get Fooled By A Cheaper Price

Thanks for the tip!

BigAL
12-24-2005, 4:57 PM
There Are Two Types Of Carry Handle
Make Sure You Get The One That Is For F Marked
Front Site Base
Don't Get Fooled By A Cheaper Price


Just for clarification. The taller F marked front sight is designed to work with detachable carry handles. There are not 2 different types of detachable carry handles which is how I read your post. When Colt developed the flat top, the result was a taller rear sight, mandating a taller front sight to compensate. They diud this by using the same forging but milling the shelf a bit higher. Most other non-military makers did not follow suit but instead installed taller front sight posts instead as this is a much cheaper solution.

So if you get an upper w/ detachable carry handle a F front sight is nice but not the end of the world. A taller front sight post will get the job done just as well but it isn't "mil-spec". And if you go A1 or A2 sights the standard front sight height is just fine.

PIRATE14
12-25-2005, 9:20 AM
Well Bushmaster was machining their handles to diff specs as well as a few others to match the FSB they were using......there have been tons of discussions on AR15.com on the subject and measurements were taken.....so there are two sizes.......not an expert but I did stay at a holiday inn last night.....:)

You can swap out front site posts but why not just by the right parts to begin with for a few more bucks

blacklisted
12-25-2005, 1:02 PM
What's the verdict on the Wylde chamber? Is it safe to fire 5.56 and .223 in it? I heard it was sort of in between milspec and SAAMI spec. I'm asking this because the RRA Varmint Upper I'm looking at has a Wylde chamber, and I would like to be able to shoot 5.56 in it as well.

BigAL
12-25-2005, 2:29 PM
Well Bushmaster was machining their handles to diff specs as well as a few others to match the FSB they were using......there have been tons of discussions on AR15.com on the subject and measurements were taken.....so there are two sizes.......not an expert but I did stay at a holiday inn last night.....:)

You can swap out front site posts but why not just by the right parts to begin with for a few more bucks

We'll that's interesting. I guess this is the sort of stuff that happens over the decades when different companies reverse engineer AR-15 parts and wind up finding different solutions to the same problem. That's one of the things about AR15s; there are so many options which increase modularity but also at the cost of increase complexity and wondering "will part A from company X work with part B from company Y". Just like the above poster's question about the Wylde chamber vs. 5.56 vs. .223 vs. 5.56 "match". After a while it can all make your head spin. I can't imagine what I'd do w/o online resources like Arfcom when building an AR-15.