Moving to an Ar type

2

Replies

  • ZeeZee Senior Member Posts: 20,620 Senior Member
    Wambli Ska wrote: »
    Why? Because it impossible to impart knowledge without being an ass about it?

    Did you leave Linefinder out of that quote for any particular reason? I read as he agreed with Pegasus.

    Just curious.
    "To Hell with efficiency, it's performance we want!" - Elmer Keith
  • BigDanSBigDanS Senior Member Posts: 6,803 Senior Member
    Wouldn’t it be nice if manufacturers stepped up to the plate and marked barrels .223 safe for 5.56?

    D
    "A patriot is mocked, scorned and hated; yet when his cause succeeds, all men will join him, for then it costs nothing to be a patriot." Mark Twain
    Alcohol, Tobacco, Firearms and Explosives.... now who's bringing the hot wings? :jester:
  • BigDanSBigDanS Senior Member Posts: 6,803 Senior Member
    cpj wrote: »
    I'd wager (throwing out experience, specs, blah blah blah ) that most garden variety AR chambers already are. Simply for lawsuit protection. Of course that would take making a chamber cast of a bunch of them, so that's speculation on my part.

    Even though we mostly know .223 guns fire 5.56 well, gun makers can hide behind " they shot 5.56, so we aren't responsible." And, for the record, my Weatherby Vanguard MOA .223 shoots 5.56 better than .223. The PMC X-Tac is 5.56.



    D
    "A patriot is mocked, scorned and hated; yet when his cause succeeds, all men will join him, for then it costs nothing to be a patriot." Mark Twain
    Alcohol, Tobacco, Firearms and Explosives.... now who's bringing the hot wings? :jester:
  • tennmiketennmike Senior Member Posts: 26,106 Senior Member
    OJR, from what I see as your end use, a barrel with a twist rate of 1-8" or 1-9" will be good for the more common hunting (varmint) bullets of up to 70 grains, and for the animals you mentioned, the 55-65 grain ones should be entirely adequate for the job, and the terminal ballistics are just nasty on small critters. And since you're handloading for accuracy, just get the .223 chambered rifle. No sense getting the 'generous' 5.56x45 chamber or the tradeoff Wylde chamber.

    Regarding shooting 5.56x45 milsurp ammo in a .223 chambered rifle, I have a Colt H-Bar and a Colt Sporter, both post ban, that shot nothing but milsurp ammo for most of their lives, and still do. They've shot some regular .223 bulk ammo, but not all that much. They didn't know the difference, and just digested them. The ammo I had/have is standard ball, not the steel core crapola. That stuff is about as accurate as hand grenades and horseshoes; close but no see-gar. I shot some of the steel core stuff, about a hundred rounds through both rifles, and they both HATE it.
    If the U.S. Congress was put in charge of the Sahara Desert, there would be a shortage of sand in under six months.



  • orchidmanorchidman Senior Member Posts: 7,731 Senior Member
    First it was shooting handguns, now it is those evil black rifles ojr.

    Next thing is Darth Vader will embrace you as his son............:nono::nono::nono::wink:
    Still enjoying the trip of a lifetime and making the best of what I have.....
  • Gene LGene L Senior Member Posts: 10,248 Senior Member
    BigDanS wrote: »
    Wouldn’t it be nice if manufacturers stepped up to the plate and marked barrels .223 safe for 5.56?

    D

    Not enough room on a 16" barrel for that amount of script. It's just not necessary anyway.
    Not too many problems you can't fix
    With a 1911 and a 30-06
  • bisleybisley Senior Member Posts: 10,653 Senior Member
    orchidman wrote: »
    First it was shooting handguns, now it is those evil black rifles ojr.

    Next thing is Darth Vader will embrace you as his son............:nono::nono::nono::wink:

    You mean he is allowed to have a handgun and a suppressor???? Doesn't your government know that only assassins need such equipment?
  • jbp-ohiojbp-ohio Senior Member Posts: 9,560 Senior Member
    Wambli Ska wrote: »
    Actually SIGal you’ve been told a myth that somehow survives though many reputable folks have debunked it. Over the years several threads here have been dedicated to this topic and the consensus is that as a group probably tens of thousands (maybe even hundreds of thousands) rounds of 5.56 and .223 have been fired through our guns without caring much about what is stamped on the barrel. My personal ONLY instance when I had a problem was a failure to chamber some old steel cased Wolf ammo into my Remington 700 chambered in .223. The ammo was crap anyway and jammed my buddy’s AR every other shot so we were just looking to dispose of it and I didn’t even stop to figure out what the issue was so I can’t even difinitively tell you it was a case dimmesion issue.

    So maybe there might be some accuracy issues between them when firing factory ammo but from a practical perspective they are interchangeable. That being said I’m sure you’ll find a million posts somewhere else preaching potential catastrophe if one searches enough...

    So......... Smith & Wesson prints myths in their manuals???
    WARNING: NEVER USE AMMUNITION MARKED 5.56
    NATO IN A FIREARM MARKED .223 REM. FAILURE TO
    ADHERE TO THIS WARNING MAY CAUSE EXCESSIVE
    PRESSURE WHICH CAN DAMAGE OR EVEN RUPTURE YOUR
    FIREARM, CAUSING PERSONAL INJURY, DEATH OR PROPERTY
    DAMAGE.

    http://www.smith-wesson.com/wcsstore...10-10-2010.pdf page 9
    "The democracy will cease to exist when you take away from those who are willing to work and give to those who would not." Thomas Jefferson
  • Big ChiefBig Chief Senior Member Posts: 32,995 Senior Member
    Hey, could this happen :yikes: :tooth:

    https://www.youtube.com/watch?v=xhgyJMhQFbA
    It's only true if it's on this forum where opinions are facts and facts are opinions
    Words of wisdom from Big Chief: Flush twice, it's a long way to the Mess Hall
    I'd rather have my sister work in a whorehouse than own another Taurus!
  • Big ChiefBig Chief Senior Member Posts: 32,995 Senior Member
    OK my Hornady (9th edition pg 157) manual list two different sections for the .223 Rem. One says Service Rifle where they used a Colt AR 15 W/ Citadel bbl the other uses a Rem 700. Then they list a 5.56 NATO using a Bushmaster XM15-E25 as the rifle used.

    They address this debate briefly: "It is not recommended to shoot 5.56 NATO ammunition in a .223 Remington chamber. Firing 5.56 NATO (higher pressure) in a .223 Remington (shorter throat) rifle can cause pressure related damage that could lead to injury." (9th edition pg 157)

    I'd be less inclined to fire 5.56 in a bolt rifle chambered in .223 than another AR 15 marked .223. That bolt and caming action can really shove a cartridge tight in the chamber throat and even the bullets ogive into the rifling you may not notice using your bolt rifle.

    I say use what is stamped on the rifle and in the owners manual to be safe if you are not sure if your rifle can can/will handle both.
    It's only true if it's on this forum where opinions are facts and facts are opinions
    Words of wisdom from Big Chief: Flush twice, it's a long way to the Mess Hall
    I'd rather have my sister work in a whorehouse than own another Taurus!
  • Big ChiefBig Chief Senior Member Posts: 32,995 Senior Member
    Of course, if you have a 5.56 NATO rated/cut chamber you are good to go using .223 ammo, unless as Hornady also pointed out there is some cycling issues.
    It's only true if it's on this forum where opinions are facts and facts are opinions
    Words of wisdom from Big Chief: Flush twice, it's a long way to the Mess Hall
    I'd rather have my sister work in a whorehouse than own another Taurus!
  • Big ChiefBig Chief Senior Member Posts: 32,995 Senior Member
    Now, are we gonna get into the .308 Win vs 7.62 NATO debate? Where the general consensuses by many is do not fire .308 Win in military spec 7.62 chambered gun because it usually is loaded to higher pressures, but it is OK to fire 7.62 military in a .308 Win gun. Even though SAMMI has said it should be safe to do so.

    https://en.wikipedia.org/wiki/7.62%C3%9751mm_NATO
    It's only true if it's on this forum where opinions are facts and facts are opinions
    Words of wisdom from Big Chief: Flush twice, it's a long way to the Mess Hall
    I'd rather have my sister work in a whorehouse than own another Taurus!
  • tennmiketennmike Senior Member Posts: 26,106 Senior Member
    The major difference, that matters, between the .223 Rem. And 5.56x45 NATO chamber is the leade. The 5.56 has a longer throat that allows the bullet more jump before it engages the rifling. The Wylde chamber has the longer leade of the 5.56 chamber, among other things.

    The main reason, if you can call it a reason, 5.56 ammo is higher pressure is because that is the only way it can attain the unrealistic velocity it was stuck with when it was going through military trials. That higher pressure meant higher velocity which was needed to stabilize the bullet in the slow twist barrels of the M-16 to make the barely stabilized bullet tumble when it hit its fleshy target. And somewhere along the way the twist rate was increased to stabilize the newer heavier bullets, but the ignorant high pressure requirement wasn't changed to reflect the changes in twist rate and bullets used. The military arms bunch at the armories do some really stupid stuff. And they've been doing it since Harper's Ferry was built way back before the Civil War.
    If the U.S. Congress was put in charge of the Sahara Desert, there would be a shortage of sand in under six months.



  • TrueTone911TrueTone911 Senior Member Posts: 6,045 Senior Member
    SIGgal wrote: »
    Thank you Wambli for the correction. I am just a young uninformed female here, I will take my lumps from the guys. Just trying to be helpful and learn, and yes, I appreciate the input good or otherwise.

    Got nothin to do with being young or female. I was under the impression that 5.56 ammo should not be fired in a .223...and I am neither young or female.
  • jbp-ohiojbp-ohio Senior Member Posts: 9,560 Senior Member
    Got nothin to do with being young or female. I was under the impression that 5.56 ammo should not be fired in a .223...and I am neither young or female.

    Well, it's a good thing you are here to learn better...... Even though the Sporting Arms and Ammunition Manufacturers Institute (SAMMI) says its unsafe, but what would they know?

    http://saami.org/specifications_and_information/publications/download/SAAMI_ITEM_211-Unsafe_Arms_and_Ammunition_Combinations.pdf
    "The democracy will cease to exist when you take away from those who are willing to work and give to those who would not." Thomas Jefferson
  • TrueTone911TrueTone911 Senior Member Posts: 6,045 Senior Member
    jbp-ohio wrote: »
    Well, it's a good thing you are here to learn better...... Even though the Sporting Arms and Ammunition Manufacturers Institute (SAMMI) says its unsafe, but what would they know?

    http://saami.org/specifications_and_information/publications/download/SAAMI_ITEM_211-Unsafe_Arms_and_Ammunition_Combinations.pdf

    That's good enough for me. I don't care if no examples of a problem can be found. I don't want to be the first example.
  • AxeAxe Member Posts: 375 Member
    That's good enough for me. I don't care if no examples of a problem can be found. I don't want to be the first example.

    I don't want to be the one with a non operational rifle due to firing the wrong ammo in my rifles either, so I will stick with 5.56 since mine are ok with it..... and stamped for it. The difference may be a minor one for weapons not stamped 5.56 but I wouldn't want to push limits with that stuff. Injury or death to just damage to the rifle, I don't chance that stuff.
  • knitepoetknitepoet Senior Member Posts: 18,860 Senior Member
    Wambli Ska wrote: »
    Hey at the end, when in doubt follow the instructions on the box. or YOYO
    FIFY :rotflmao:

    and if you aren't familiar with the acronym "You're On Your Own"

    Normally proceeded by "AMF" (Adios My Friend)
    Seven Habits of Highly Effective Pirates, Rule #37: There is no “overkill”. There is only “open fire” and “I need to reload”.


  • TrueTone911TrueTone911 Senior Member Posts: 6,045 Senior Member
    When in doubt...RTFI


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  • Big ChiefBig Chief Senior Member Posts: 32,995 Senior Member
    When in doubt...RTFI


    RTFI :confused: ............Read The Forum Intensively :tooth: :roll2: :roll2:
    It's only true if it's on this forum where opinions are facts and facts are opinions
    Words of wisdom from Big Chief: Flush twice, it's a long way to the Mess Hall
    I'd rather have my sister work in a whorehouse than own another Taurus!
  • PegasusPegasus Senior Member Posts: 2,613 Senior Member
    Let me jump back in with both feet here. I was overwhelmed at the office yesterday and could not give this the attention it deserved.

    You will notice that in answer #10. I was the one who first introduced the chambering of the rifle into this discussion. I described the Wylde specifically and made some comments about the various other chamberings.

    OJR followed up with a “last” question about the Wylde and reloading and the use of NATO 5.56mm ammo, saying that he doubted he would get any of that ammo to shoot.

    Knitepoet added some further thoughts and provided a link to a Wikipedia article.

    In post 18, I responded to OJR’s “last question” in some depth, because reloading.

    Then an hour later, SIGgal jumped in with the statement:
    “5.56 NATO ammo really should not be fired from a rifle chambered for .223 because it is a hotter round and can damage your barrel over time from what I am told.

    This was right after numerous other answers talking about Wylde and also the fact OJR had stated was highly unlikely to use 5.56 in the first place.

    Just to be clear however, the added pressure, if any that would be encountered using a 5.56 round in a .223 chamber would cause problems for the AR-15 bolt and other parts, not the barrel, not like causing it to peel like a banana or expand the throat. You can't "damage a barrel" with a "hotter round." (More on this later.)

    Others have talked here about using 5.56 in a .223 chamber. A true .223 chamber would really only ever be found in a bolt action rifle and rarely, if ever, in a factory semi-auto like an AR-15. The reason the Wylde chamber was invented was competition. Bill Wylde is a long-time Highpower competitor and when the AR-15/M-16 supplanted the M-14/M1A in Service Rifle competition in 1996, people flocked to it in droves. The regular 5.56NATO chambering (the one commonly used in AR-15s) is designed to feed ammo reliably under adverse conditions, so the dimensions are generous. A .223 Rem chambering is not the most reliable for semi-autos and in Service Rifle there are rapid fire stages. The Wylde chamber is designed with the generous measurements for the body of the case for semi-auto feeding but as I explained earlier, the leade is very tight like a .223 chamber and longer than a .223 to accept the 80gr bullets that allowed the M16/AR-15 to dominate at Camp Perry.

    The AR-15 mostly comes in one of two chamberings: 5.56NATO and the Wylde chamber or any number of variations of it with another name. Even the “Wylde” has variations depending on who offers it and the reamer they are using and so on.

    The leade is that area in front of the case mouth, just before the rifling begins and it is the diameter of the bullet .224 or larger for the NATO chamber. When the round is chambered, the case mouth sits just short of the leade in a larger diameter area and the bullet that protrudes from the case mouth is now in the leade and its ogive may well be in the rifled bore.

    The area where the rifling begins is marked by the protrusion of something called the lands. This is in contrast to the grooves. The lands are at the bore diameter and the grooves are at the bullet diameter. So, in a .308 rifle, the lands are at .300 inch and the grooves are an extra .004 into it, or at .308 inch. In an AR, the lands are at .216 and the grooves are at .224inch.

    When you look at a bullet, the tip of the bullet is called the meplat, the section from the meplat to the maximum diameter of the bullet body is called the ogive. At the rear of the bullet you have the boat tail, if the bullet has one. When the cartridge is chambered, the distance between the lands and the bullet ogive approaching maximum diameter, is something that is of interest to some. The folks looking for ultimate precision out of their rifle/ammo combination will usually try to keep this distance as small as possible or may just play around looking for the perfect combination.

    It is also “well-known” that if your bullet touches the lands when the cartridge is chambered, there could be additional pressure at ignition time because the bullet would not have any momentum as it starts to engrave in the lands. This is the thing that we are talking about here with respect to the additional pressure of a 5.56NATO round fired in a .223 chamber. But this requires that the .223 chamber be cut to the minimum leade for that to have any chance of generating additional pressure.

    Let me get back to the bullet for a second. In a spitzer-type bullet, there are essentially two ogive forms: tangent and secant. The secant type is very straight and is found in VLD (very low drag) bullets. These bullets are also longer than tangent type bullets of the same weight. The Hornady A-max and its follow-on are good examples of these bullets. The match bullets I favor are also secant type ogives. The other type is a tangent type ogive, where the ogive is a curve (or a tangent from the line) to the meplat. The M855 bullet found in 5.56NATO ammo is a tangent type ogive. Berger introduced a third type they called hybrid because it has some of the tangent and some of the secant profiles in the ogive.

    You can safely seat secant type ogive bullets with the maximum diameter of the bullet at the lands or even into the lands because the resistance of the bullet to engraving is gradual and no extra pressure is generated. On the other hand, tangent type ogive bullets by virtue of have a more bulbous ogive present more resistance at initial engraving, and may thus cause more pressure at that time.

    I should also point out that the angle of the lands has a lot to do with this. The lands usually have an angle between 2 and 4 degrees starting from the leade; they don’t just appear in their full .004 size. As you would expect there are discussions about which angle is better for precision. (We like to talk minutiae as much as we can.) The problem is that after several firings, this area of the barrel, called the throat, is affected up by the heat, pressure and so on and the lands begin to recede. If they recede too far, accuracy may suffer. This is the main area where a barrel is “shot out.”

    Do you remember when I said earlier that you can’t damage a barrel by firing a “hotter round?” In actuality, every round damages the barrel in which it is fired. Some calibers do a better job of eating up barrels than others. The .243 Winchester, the .220 Swift, the 6.5-284, etc., are well-known for literally consuming barrels within 1000 rounds.

    Back to the 5.56/.223, as the throat erosion occurs whatever extra pressure there may have been using 5.56NATO ammo in a .223 Remington chamber simply vanishes. It doesn’t take much throat erosion for that to occur.

    In my decades of shooting, competing and web surfing, I have never heard of, read about let alone, seen a case of a .223 Remington-chambered rifle blowing up or be damaged by firing a 5.56NATO round. Does this mean it has never happened? Since you can’t prove a negative, I have no way of knowing. But somewhere along the way, someone came up with that concept and it has taken hold. Some years back, this was shouted from every rooftop and keyboard, but over the last several years, it has been pretty much debunked. Does that mean that I urge the use of 5.56NATO in a tight .223 chamber? Absolutely not; I know 5.56NATO ammo is grossly inaccurate and I would not ever use it by choice. There is MUCH better ammo than that crap you can use for any situation.

    Now, let me present you with a couple other subjects that are sure to generate mirth and merriment on this forum. For maximum effectiveness, be sure to start them by stating whatever you read on a forum somewhere:
    Barrel break-in procedures.
    Barrel cleaning procedures.
    And of course, everybody’s favorite punching bag, the .270 caliber.
  • TrueTone911TrueTone911 Senior Member Posts: 6,045 Senior Member
    Big Chief wrote: »
    RTFI :confused: ............Read The Forum Intensively :tooth: :roll2: :roll2:


    Read the bleeping instructions


    Sent from my iPhone using Tapatalk Pro
  • bisleybisley Senior Member Posts: 10,653 Senior Member
    Pegasus wrote: »
    ...I should also point out that the angle of the lands has a lot to do with this. The lands usually have an angle between 2 and 4 degrees starting from the leade; they don’t just appear in their full .004 size. As you would expect there are discussions about which angle is better for precision. (We like to talk minutiae as much as we can.) The problem is that after several firings, this area of the barrel, called the throat, is affected up by the heat, pressure and so on and the lands begin to recede. If they recede too far, accuracy may suffer. This is the main area where a barrel is “shot out.”

    Do you remember when I said earlier that you can’t damage a barrel by firing a “hotter round?” In actuality, every round damages the barrel in which it is fired. Some calibers do a better job of eating up barrels than others. The .243 Winchester, the .220 Swift, the 6.5-284, etc., are well-known for literally consuming barrels within 1000 rounds.

    Back to the 5.56/.223, as the throat erosion occurs whatever extra pressure there may have been using 5.56NATO ammo in a .223 Remington chamber simply vanishes. It doesn’t take much throat erosion for that to occur...

    Excellent post - very informative and completely understandable. Your 'technical writing' skills are very good.

    The part I bolded alarmed me, initially. Then, I realized that 1000 rounds = 50 boxes of ammo. How many of us will ever shoot 50 boxes of ammo through our deer rifles? Thinking about it, even in my own worst case scenarios, I have probably never fired even 100 rounds during load development. Once that is done, I typically fire less than 5 rounds per year through my deer hunting rifles. In fact, in recent years, if everything goes according to plan, I fire one cold bore shot to confirm zero, then one shot each for two deer, if lucky enough to see two worthy deer in my 'kill zone.' The last couple of years, I fired the cold bore shot, and no more, so I don't even maintain that low average number.

    But, if I do have good luck, and manage to average 5 rounds per year, I can still hunt with my .243 for 180 years, after working up the load. That gives me a lot of leeway for frivolous target practice, etc., especially since I have several deer capable rifles to choose from. So, really, only prairie dog shooters and competition shooters need to concern themselves very much with the 1000 round standard. It reminds me of my lawnmower research. When you discover that the manufacturer only wants to make an engine that lasts 1000 hours, or whatever, it seems low, because most of us look at lawnmowers as high use, high maintenance tools. In reality, most home owners will spend much less than 100 hours a year on their lawnmower, so even a cheap lawnmower will last ten years on a regularly mowed area, if properly maintained.
  • snake284snake284 Senior Member Posts: 21,855 Senior Member
    bisley wrote: »
    Excellent post - very informative and completely understandable. Your 'technical writing' skills are very good.

    The part I bolded alarmed me, initially. Then, I realized that 1000 rounds = 50 boxes of ammo. How many of us will ever shoot 50 boxes of ammo through our deer rifles? Thinking about it, even in my own worst case scenarios, I have probably never fired even 100 rounds during load development. Once that is done, I typically fire less than 5 rounds per year through my deer hunting rifles. In fact, in recent years, if everything goes according to plan, I fire one cold bore shot to confirm zero, then one shot each for two deer, if lucky enough to see two worthy deer in my 'kill zone.' The last couple of years, I fired the cold bore shot, and no more, so I don't even maintain that low average number.

    But, if I do have good luck, and manage to average 5 rounds per year, I can still hunt with my .243 for 180 years, after working up the load. That gives me a lot of leeway for frivolous target practice, etc., especially since I have several deer capable rifles to choose from. So, really, only prairie dog shooters and competition shooters need to concern themselves very much with the 1000 round standard. It reminds me of my lawnmower research. When you discover that the manufacturer only wants to make an engine that lasts 1000 hours, or whatever, it seems low, because most of us look at lawnmowers as high use, high maintenance tools. In reality, most home owners will spend much less than 100 hours a year on their lawnmower, so even a cheap lawnmower will last ten years on a regularly mowed area, if properly maintained.

    I've had mowers last 20 years and didn't do much to maintain it. Changed the oil once every 10 years whether it needed it or not.

    :jester:
    Daddy, what's an enabler?
    Son that's somebody with nothing to do with his time but keep me in trouble with mom.
  • bisleybisley Senior Member Posts: 10,653 Senior Member
    snake284 wrote: »
    I've had mowers last 20 years and didn't do much to maintain it. Changed the oil once every 10 years whether it needed it or not.

    :jester:

    Marry a woman who loves to mow, then get back to me in 20 years and tell me how many mowers you have bought. :tooth:
  • PegasusPegasus Senior Member Posts: 2,613 Senior Member
    bisley wrote: »
    Excellent post - very informative and completely understandable. Your 'technical writing' skills are very good.

    The part I bolded alarmed me, initially. Then, I realized that 1000 rounds = 50 boxes of ammo. How many of us will ever shoot 50 boxes of ammo through our deer rifles? Thinking about it, even in my own worst case scenarios, I have probably never fired even 100 rounds during load development. Once that is done, I typically fire less than 5 rounds per year through my deer hunting rifles. In fact, in recent years, if everything goes according to plan, I fire one cold bore shot to confirm zero, then one shot each for two deer, if lucky enough to see two worthy deer in my 'kill zone.' The last couple of years, I fired the cold bore shot, and no more, so I don't even maintain that low average number.

    But, if I do have good luck, and manage to average 5 rounds per year, I can still hunt with my .243 for 180 years, after working up the load. That gives me a lot of leeway for frivolous target practice, etc., especially since I have several deer capable rifles to choose from. So, really, only prairie dog shooters and competition shooters need to concern themselves very much with the 1000 round standard. It reminds me of my lawnmower research. When you discover that the manufacturer only wants to make an engine that lasts 1000 hours, or whatever, it seems low, because most of us look at lawnmowers as high use, high maintenance tools. In reality, most home owners will spend much less than 100 hours a year on their lawnmower, so even a cheap lawnmower will last ten years on a regularly mowed area, if properly maintained.

    Thank you for the kind words.

    You are absolutely correct; the vast majority of shooters will never wear out a barrel. Well, some of the AR shooters might, the ones who take pleasure at doing magazine dumps, but then again, they would never know when their barrel is shot out to begin with. Also, if you do like to abuse an AR-15 that way, make sure your barrel is chrome-lined; they last a bit longer.

    Going back to the definition of "shot out barrel," your characterization of such users as being prairie dog shooters and competition shooters is exactly on the money. Their definition of shot-out barrel is probably not what most shooters would define as "shot or worn out". In my case, I roll off the barrel of my .308 match rifle at 4,000 rounds. My barrels are stainless steel, heavy Palma contour for heat control and bead blasted for faster cooling. Plus I have devices that I place in the bore to cool the barrel after a string. A goo .308 barrel used that way should hold its guilt-edged accuracy for 5000+ rounds easily enough. I don't let it get close to that and SS barrels have nasty characteristics when they start to go bad. They can and do let go from one match to the next. So, I always have a replacement barrel ready. When that one goes on the rifle, I order another pair from Krieger.

    Now that I have slowed down a lot in competition, a barrel should last me two years or more. Before, it was one a year or so.
  • PegasusPegasus Senior Member Posts: 2,613 Senior Member
    I will add that the F-Open guys used to roll off their barrels at 1000 rounds or so when they were shooting the 6.5X284. Imagine consuming 10-20% of your barrel life doing load development. They had to get creative doing that. Now that they have moved on to the 7mms, barrel life is closer to 2500/3000 rounds.
  • FisheadgibFisheadgib Senior Member Posts: 5,696 Senior Member
    Pegasus wrote: »
    Let me jump back in with both feet here. I was overwhelmed at the office yesterday and could not give this the attention it deserved.

    You will notice that in answer #10. I was the one who first introduced the chambering of the rifle into this discussion. I described the Wylde specifically and made some comments about the various other chamberings.

    OJR followed up with a “last” question about the Wylde and reloading and the use of NATO 5.56mm ammo, saying that he doubted he would get any of that ammo to shoot.

    Knitepoet added some further thoughts and provided a link to a Wikipedia article.

    In post 18, I responded to OJR’s “last question” in some depth, because reloading.

    Then an hour later, SIGgal jumped in with the statement:
    “5.56 NATO ammo really should not be fired from a rifle chambered for .223 because it is a hotter round and can damage your barrel over time from what I am told.

    This was right after numerous other answers talking about Wylde and also the fact OJR had stated was highly unlikely to use 5.56 in the first place.

    Just to be clear however, the added pressure, if any that would be encountered using a 5.56 round in a .223 chamber would cause problems for the AR-15 bolt and other parts, not the barrel, not like causing it to peel like a banana or expand the throat. You can't "damage a barrel" with a "hotter round." (More on this later.)

    Others have talked here about using 5.56 in a .223 chamber. A true .223 chamber would really only ever be found in a bolt action rifle and rarely, if ever, in a factory semi-auto like an AR-15. The reason the Wylde chamber was invented was competition. Bill Wylde is a long-time Highpower competitor and when the AR-15/M-16 supplanted the M-14/M1A in Service Rifle competition in 1996, people flocked to it in droves. The regular 5.56NATO chambering (the one commonly used in AR-15s) is designed to feed ammo reliably under adverse conditions, so the dimensions are generous. A .223 Rem chambering is not the most reliable for semi-autos and in Service Rifle there are rapid fire stages. The Wylde chamber is designed with the generous measurements for the body of the case for semi-auto feeding but as I explained earlier, the leade is very tight like a .223 chamber and longer than a .223 to accept the 80gr bullets that allowed the M16/AR-15 to dominate at Camp Perry.

    The AR-15 mostly comes in one of two chamberings: 5.56NATO and the Wylde chamber or any number of variations of it with another name. Even the “Wylde” has variations depending on who offers it and the reamer they are using and so on.

    The leade is that area in front of the case mouth, just before the rifling begins and it is the diameter of the bullet .224 or larger for the NATO chamber. When the round is chambered, the case mouth sits just short of the leade in a larger diameter area and the bullet that protrudes from the case mouth is now in the leade and its ogive may well be in the rifled bore.

    The area where the rifling begins is marked by the protrusion of something called the lands. This is in contrast to the grooves. The lands are at the bore diameter and the grooves are at the bullet diameter. So, in a .308 rifle, the lands are at .300 inch and the grooves are an extra .004 into it, or at .308 inch. In an AR, the lands are at .216 and the grooves are at .224inch.

    When you look at a bullet, the tip of the bullet is called the meplat, the section from the meplat to the maximum diameter of the bullet body is called the ogive. At the rear of the bullet you have the boat tail, if the bullet has one. When the cartridge is chambered, the distance between the lands and the bullet ogive approaching maximum diameter, is something that is of interest to some. The folks looking for ultimate precision out of their rifle/ammo combination will usually try to keep this distance as small as possible or may just play around looking for the perfect combination.

    It is also “well-known” that if your bullet touches the lands when the cartridge is chambered, there could be additional pressure at ignition time because the bullet would not have any momentum as it starts to engrave in the lands. This is the thing that we are talking about here with respect to the additional pressure of a 5.56NATO round fired in a .223 chamber. But this requires that the .223 chamber be cut to the minimum leade for that to have any chance of generating additional pressure.

    Let me get back to the bullet for a second. In a spitzer-type bullet, there are essentially two ogive forms: tangent and secant. The secant type is very straight and is found in VLD (very low drag) bullets. These bullets are also longer than tangent type bullets of the same weight. The Hornady A-max and its follow-on are good examples of these bullets. The match bullets I favor are also secant type ogives. The other type is a tangent type ogive, where the ogive is a curve (or a tangent from the line) to the meplat. The M855 bullet found in 5.56NATO ammo is a tangent type ogive. Berger introduced a third type they called hybrid because it has some of the tangent and some of the secant profiles in the ogive.

    You can safely seat secant type ogive bullets with the maximum diameter of the bullet at the lands or even into the lands because the resistance of the bullet to engraving is gradual and no extra pressure is generated. On the other hand, tangent type ogive bullets by virtue of have a more bulbous ogive present more resistance at initial engraving, and may thus cause more pressure at that time.

    I should also point out that the angle of the lands has a lot to do with this. The lands usually have an angle between 2 and 4 degrees starting from the leade; they don’t just appear in their full .004 size. As you would expect there are discussions about which angle is better for precision. (We like to talk minutiae as much as we can.) The problem is that after several firings, this area of the barrel, called the throat, is affected up by the heat, pressure and so on and the lands begin to recede. If they recede too far, accuracy may suffer. This is the main area where a barrel is “shot out.”

    Do you remember when I said earlier that you can’t damage a barrel by firing a “hotter round?” In actuality, every round damages the barrel in which it is fired. Some calibers do a better job of eating up barrels than others. The .243 Winchester, the .220 Swift, the 6.5-284, etc., are well-known for literally consuming barrels within 1000 rounds.

    Back to the 5.56/.223, as the throat erosion occurs whatever extra pressure there may have been using 5.56NATO ammo in a .223 Remington chamber simply vanishes. It doesn’t take much throat erosion for that to occur.

    In my decades of shooting, competing and web surfing, I have never heard of, read about let alone, seen a case of a .223 Remington-chambered rifle blowing up or be damaged by firing a 5.56NATO round. Does this mean it has never happened? Since you can’t prove a negative, I have no way of knowing. But somewhere along the way, someone came up with that concept and it has taken hold. Some years back, this was shouted from every rooftop and keyboard, but over the last several years, it has been pretty much debunked. Does that mean that I urge the use of 5.56NATO in a tight .223 chamber? Absolutely not; I know 5.56NATO ammo is grossly inaccurate and I would not ever use it by choice. There is MUCH better ammo than that crap you can use for any situation.

    Now, let me present you with a couple other subjects that are sure to generate mirth and merriment on this forum. For maximum effectiveness, be sure to start them by stating whatever you read on a forum somewhere:
    Barrel break-in procedures.
    Barrel cleaning procedures.
    And of course, everybody’s favorite punching bag, the .270 caliber.


    You must like the sound of your own typing because I doubt many if anyone is gonna read all of that. Since you felt impelled to cover allmost all of "rifle 101" go ahead and add that the wide part that's wood or plastic is usually the butt and the metal pipe thingy with a hole at the end is the barrel since you seem to think most folks here are at that level of firearms knowledge.
    snake284 wrote: »
    For my point of view, cpj is a lot like me
    .
  • PegasusPegasus Senior Member Posts: 2,613 Senior Member
    Fisheadgib wrote: »
    You must like the sound of your own typing because I doubt many if anyone is gonna read all of that. Since you felt impelled to cover allmost all of "rifle 101" go ahead and add that the wide part that's wood or plastic is usually the butt and the metal pipe thingy with a hole at the end is the barrel since you seem to think most folks here are at that level of firearms knowledge.

    Bite me. It wasn't meant for you as I wrote it very quickly and without pictures.
  • BigslugBigslug Senior Member Posts: 7,042 Senior Member
    I'd take the money from your CZ 527, and buy a CZ 527.

    For an AR, to be owned not in the US market of massive aftermarket support, I'd buy a Colt and be done. It's the full-on, built to military code rifle. I inspect a lot of police officer's personal purchases prior to their being used in the field. The Colt inspections are boring - typically if there's something not right out of the box, it's on a rifle made by someone else.

    Lack of chrome lining is part of why the early rifles had trouble in Vietnam - chamber pitting (comparatively minor), coupled with a crust-generating batch of powder and the early-generation, lighter tension extractor springs made for a problematic system. You give up a little accuracy with chrome plating, but not that you'd notice in a field rifle.

    Truthfully though, you sold the right gun for the job.
    WWJMBD?

    "Nothing is safe from stupid." - Zee
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