AR not pulling shot cases out of barrel - Page 2

ShootistPRS · February 19, 2017, 04:18 PM

I have to comment on two pieces of information that have been made as they conflict with facts as I know them.
1. Wylde chambers: Wylde chambers are larger than the 223/556 chambers. The length of a SAAMI 223/556 chamber is 1.760 from base to mouth while the Wylde chamber is at least 1.773 (minimum). The SAAMI diameter of the shoulder to body junction is .354 for 223/556 while the Wylde chamber is .3572 The chamber mouth diameter for SAAMI chamber is .253, the Wylde chamber mouth is .2558; The Wylde chamber was designed so the 223/556 cartridges could be fired interchangeably without considerations for free bore which is the difference in the chambers of 223 and 556.

On chamber lube:
2. Every reloading book and manual I have read in the past 45 years state that oiling a chamber or cartridge increases the back thrust on the bolt and for that reason it is imperative that chambers and cases be clean and dry when loading.
If anyone can point to a reputable article that states otherwise I would be happy to see it.

These two items are not intended to start arguments, rather to put out factual information to those who are new to reloading and the AR platform and its different attributes.

I steered away from the Wylde chamber simply because it would cause the cartridge to expand more when fired and therefore worked more when resized causing earlier failure of the cases.

ed308 · February 19, 2017, 05:40 PM

Hmm..., I always thought 5.56 NATO chamber has a longer throat compared to the .223 chamber so it can handle the higher pressure produced by the 5.56 NATO round. With that said, .223 is usually the more accurate than 5.56 NATO. The Wylde chamber was designed to gain the accuracy advantages of the .223 Remington but also allow you to safely shoot 5.56 NATO without the pressure problems associated with .223. To each his own, but the Wylde is the best of both worlds IMO. But I also like to shoot the heavier bullets in my Wylde chamber barrels. And they are more accurate than my 5.56 barrels.

ShootistPRS · February 19, 2017, 06:04 PM

ED,
The throat of the 556 is longer than the 223 - that is the free bore part of the chamber. The chamber length is the distance from the bolt face to the mouth of the cartridge and the head space is the length from the bolt face to the distance to the datum of the shoulder. The Wylde camber has more head space while the 223 and 556 share the same, shorter, head space.

As far as accuracy goes there are a lot more variables and the barrel leade and quality have more to do with it than the chamber does (IMHO). There is also the point that the Wylde chamber is not specified by SAAMI so it can vary a lot more than the SAAMI standard chambers. The dimensions for the Wylde chamber that I have are from a Reamer drawing from Manson Precision Reamers. They agree with other dimensions that I have seen but this is the only one I have in my records.

Slamfire · February 20, 2017, 08:30 AM

Quote:

On chamber lube:
2. Every reloading book and manual I have read in the past 45 years state that oiling a chamber or cartridge increases the back thrust on the bolt and for that reason it is imperative that chambers and cases be clean and dry when loading.

Do you believe everything authority says? Do you have unexamined beliefs, ideas, concepts, that are contradictory and yet you accept them ?

If what the reloading books and manuals are correct, then why is there not a section telling reloaders to cut their loads for rifles with fluted chambers?

The primary reason you don't see oilers on post WW2 firearms is because of fluted chambers. Instead of oil breaking the friction between case and chamber, high pressure gas breaks the friction. If bolt thrust is bad, then fluted chambers are bad.

XTRAXN flutes the chambers of their Ar15's. It is clear they want to break the friction between case and chamber.

http://www.larue.com/xtraxn%E2%84%A2...larue-tactical

Are you aware that POF is fluting their chambers to make extraction more reliable.

https://pof-usa.com/features/e%C2%B2...ction-chamber/

All of these devices break the friction between case and chamber, which would increase "bolt thrust", and yet the firearms function more reliably when the case to chamber friction is reduced, and the bolts last as long as any other.

The increased bolt thrust concern is based 100% on an Army Ordnance coverup that is almost 100 years old. The fact that so many Gunwriters and manuals uncritically accepted an Army coverup for a century shows just what a Parrots they are. The "leaders" of the shooting community repeat uncritically what they have been told, have zero critical analysis capabilities , are totally ignorant of the history of firearms , and are ignorant of the design of firearms. History is replete with hundreds of mechanisms that required greased or lubricated cases, such as the first Mauser automatic rifle, and yet, all these experts are unaware, or if they were aware, never questioned their core beliefs. How could these mechanisms function and yet their beliefs be true? Newtonian laws of physics apply the same in manual mechanisms as well as automatic mechanisms. Load is load, F = MA in all corners of the universe.

Army coverups work, because no matter how incompetent the Army Ordnance Bureau, the shooting public is far more incompetent.

stagpanther · February 20, 2017, 08:47 AM

If fluted chambers really add to reliability--why aren't more manufacturers using them? http://www.thefirearmblog.com/blog/2...uted-chambers/

Bartholomew Roberts · February 20, 2017, 08:50 AM

Quote:

All of these devices break the friction between case and chamber, which would increase "bolt thrust", and yet the firearms function more reliably when the case to chamber friction is reduced, and the bolts last as long as any other.

Yet the two most common points of failure on an AR15 bolt are bolt lugs cracking/breaking off (usually the ones adjacent to the extractor cutout) and breaking in half at the cam pin hole. It seems bolt thrust must play some role in those types of failure.

Slamfire · February 20, 2017, 09:55 AM

Quote:

If fluted chambers really add to reliability--why aren't more manufacturers using them? http://www.thefirearmblog.com/blog/2...uted-chambers/

Probably cost. More to the point, why are manufacturer's adding flutes to their chambers if they don't do anything?

In so far as your link claiming that fluted chambers are dangerous, I don't believe the analysis for the separated case. I have fired thousands of rounds through my PTR 91, commercial and military, and have not experienced the problem that your link claims.

Now, I have fired ammunition in my non fluted chamber Garand, and experienced this:

I think what happened in your referenced link was a bad brass case that separated.

The guys at Gunboards, they have been shooting commercial ammunition through military G3 barrels for decades. This post, I believe what he is saying that excessively soft brass will have issues in a G3 barrel, but then, excessively soft brass will have issues in non fluted chambers also. But, he has fired lots of commercial brass without problems and calls the commercial ammunition warnings "myths".

http://forums.gunboards.com/archive/.../t-257569.html

Quote:

The old "don't shoot commercial ammo" through a CETME or HK-91 is a myth. When the CETME & G3 went through development, they found the fluted chamber had issues with soft brass. When fired, the brass case expands around the chamber flutes on a cushion of air. If the brass is very soft, it will expand filling the flutes and get stuck on the chamber wall. Whether it be that commercial brass is thinner than military brass... or that commercial 308 ammo is a bit hotter than 7.62 NATO... someone set forth the wive's tale not to use commercial ammo in a CETME. Even though many of us had been shooting commercial ammo in our HKs and Mars CETME's for decades with no issues. Maybe they confused the SAAMI warning not to shoot 5.56 NATO in .233 Remington chambers as carrying over to the 308 & 7.62 NATO. Steel cased ammo was thoroughly tested during development of these rifles and was found to be quite satisfactory. I actually prefer to use steel cased ammo in fluted chambers and blow back SMGs.

stagpanther · February 20, 2017, 10:09 AM

I'm not an expert--in fact, I usually claim to be the opposite--closer to the "have no clue" camp. ; ) But I do try to reason things out on my own.

Based on my limited experience, any scheme for "unlocking" a case from a chamber is essentially a device for correcting a "asymmetry" between the case contraction upon firing and the automatic bolt extraction. This "asymmetry" I believe can exist for different reasons in my experience, but the net result is the same--a "sticky" case. I believe that's why most commercial barrels tend to be over-gassed, but that's just a guess on my part. I can see why a fluted chamber might make sense for a "life or death must fire" combat weapon--but I just haven't heard of this being used widely--especially on precision rifles, and in that sector of the market I would guess cost is irrelevant if it could produce even a 1/1000th MOA improvement.

Your middle picture with the cases in hand--when I see a case like that with a gas ring forward of the neck it usually indicates a problem with chambering/headspacing in my AR's--but maybe that's just some weirdness you get with the gas blowback.

Slamfire · February 20, 2017, 10:09 AM

Quote:

All of these devices break the friction between case and chamber, which would increase "bolt thrust", and yet the firearms function more reliably when the case to chamber friction is reduced, and the bolts last as long as any other.

Yet the two most common points of failure on an AR15 bolt are bolt lugs cracking/breaking off (usually the ones adjacent to the extractor cutout) and breaking in half at the cam pin hole. It seems bolt thrust must play some role in those types of failure.

Mechanical devices are designed to a load and a service life. (plus a bunch of other requirements such as cost, weight, ergonomics, etc) No man portable small arm is designed to an infinite service life as the weapons would be too heavy. And that is a trade off, weight versus infinite service lifetime. When Stoner designed his rifle he designed it to pass a 6000 round endurance test, and he was using ammunition that produced 50,000 psia. The typical lifetime of an AR15 bolt is around 10,000 rounds of ammunition before lug cracking. Barrels generally go before then, and when military rifles go back to depot for a rebuild, anything or everything can be replaced.

Reducing ammunition pressures will increase time to fatigue failure, increasing pressures will decrease the service life of all components. However, loads for the military M16's keep on going up and up. Shortly after the M16 is in service, the load gets bumped up to 52,000 psia, then bumped up even more. Today, from what I have read, the military round is running at 68,000 psia, and yet, the basic structure has remained unchanged.

If anyone is really concerned about bolt thrust, cut your loads. More than anything else you can do, reducing cartridge pressure is most positive way to reduce bolt thrust. It is also easier on every structural element of your firearm. But I know that no one reading this is going to cut anything, because you want performance, and you will trade off part life for performance.

But the important question is, to what loads are locking mechanisms designed? Are locking mechanisms weakened assuming the cartridge case takes load? This is very easy to look up, and guess what, locking mechanism are designed to take the full load of the case and are not weakened assuming the case carries load.

Slamfire · February 20, 2017, 10:15 AM

Quote:

I can see why a fluted chamber might make sense for a "life or death must fire" combat weapon--but I just haven't heard of this being used widely--especially on precision rifles, and in that sector of the market I would guess cost is irrelevant if it could produce even a 1/1000th MOA improvement.

The F class shooters I know are using bolt rifles. By the time their finger relaxes off the trigger, pressures inside the barrel are zero, therefore for them, chamber fluting would do very little in aiding extraction. Plus, it takes specialized machinery to cut chamber flutes. I don't know the cost of an electro chemical machine, but I bet very few rifle mechanics have one!

Thread: SVT-40 chamber flutes

http://www.practicalmachinist.com/vb...flutes-218286/

ShootistPRS · February 20, 2017, 01:30 PM

The model 91 and 93 from H&K have fluted chambers, hex rifling and a delayed blow back operating system. Each part works with the others to provide a smooth functioning firearm. The fluted chambers are self cleaning because of the gas flow through the chamber when the bolt begins to open. The hex rifling allows higher velocities than standard styles of cut, hammered and button rifling. The fluted chamber lowers the amount of force it takes to extract the case and the blow-back operation is timed to operate after the pressure has dropped to a safe level. The gas that flows around the case is also used to flush any debris out of the chamber to keep the gun operating in poor conditions. It is, after all, a military firearm.

It is just one way to keep a military rifle operational in adverse conditions. It is not the only way.

2damnold4this · February 20, 2017, 03:19 PM

Quote:

1. Wylde chambers: Wylde chambers are larger than the 223/556 chambers. The length of a SAAMI 223/556 chamber is 1.760 from base to mouth while the Wylde chamber is at least 1.773 (minimum). The SAAMI diameter of the shoulder to body junction is .354 for 223/556 while the Wylde chamber is .3572 The chamber mouth diameter for SAAMI chamber is .253, the Wylde chamber mouth is .2558; The Wylde chamber was designed so the 223/556 cartridges could be fired interchangeably without considerations for free bore which is the difference in the chambers of 223 and 556.

I didn't realize that in most respects, the .223 Wylde chamber is bigger than the 5.56 chamber. I thought the Wylde chamber was tighter all around. It seems that the only dimensions that are smaller for the .223 Wylde are base to shoulder (1.4316 for the jgs223wylde, 1.4338 for the jgs5.56 and the same for the ptg.223) and the free bore diameter.

link

ed308 · February 21, 2017, 09:18 AM

5.56 Nato is larger in the free bore diameter. The .223 Remington is .2240. 5.56 Nato is .2265 and .223 Wylde is .2242. Bill Wylde developed his chamber to exploit the better accuracy of the .223 Remington chamber but without the pressure problems encountered when shooting 5.56 Nato ammo in a .223 Remington chamber barrel. The tighter .2240 free bore diameter really helps for tighter groups. And the .223 Wylde chamber likes longer and heavier bullets. Here's a link to Pacific Tool and Gauge chamber prints:

http://http://www.practicalmachinist...e-chambers.jpg

2damnold4this · February 21, 2017, 11:53 AM

I took it for granted that the Wylde chamber was tighter in most ways than the 5.56 and as ShootistPRS has pointed out, the Wylde chamber is larger with a few exceptions.

ShootistPRS · February 21, 2017, 06:51 PM

When I decided I needed a semi auto rifle for three gun I did a lot of research. The Wylde chamber was one that I originally had wrong too. From all the descriptions and that it was based on getting more accuracy, like many, I thought it was a tighter chamber. I found a reamer print for it and compared it to the SAAMI prints and decided it was not for me unless I was willing to get dies specifically made for that chambering. I eventually opted to get the 556 chamber.
I can't say whether my decision was right or not because, although I have had my gun for two weeks, I have not been able to shoot it yet! (it is really messing with my mind to have a new gun and lots of ammo sitting around the house and no way to use it)

If anyone knows of a burglar, who wants to die a horrible death at the hands of a frustrated AR owner, you can send him my way.

ed308 · February 21, 2017, 09:34 PM

ShootistPRS, what was thinking for the Nato chamber and 3 Gun? 5.56 Nato probably is the best choice for 3 Gun if using a lot of different ammo. I use a lot of different ARs for 3 Gun depending on what the course is. I'll even pull out one of my 6.8s on occasion. I did build a 18" .223 Wylde AR specifically for 3 Gun and which I run most of the time. I went with the Wylde chamber for the accuracy and reliability. I shoot a lot of Nosler 69 and 77 gr Custom Comp (HPBT) bullets and they shoot 1/2" groups in my AR15 Performance 223 Wylde barrels. They proven to be accurate and reliable for me through the years. I did take a chance a couple of weekends ago and tried Tula Steel case 77 gr HPBT just to see how they would do. I figure I would get a stuck but they ran fine. Same for my pistol too. It was kinda nice not to have to find my brass. But my FNH SLP shotgun did malfunction and for the first time I got stuck in the chamber and had to mortar it in the middle of the course. I've never mortar a shotgun in my life either LOL! It'll get a good cleaning the match next month.

ShootistPRS · February 22, 2017, 03:01 PM

Ed,
My thinking was that of using a tight chamber to work the brass less. I could have used the 223 or 556 chamber because the chamber dimensions are the same. You shouldn't use 556 ammo in the 223 camber because it has less free bore. I chose the 556 chamber so I can fire either brass equally well. The Wylde chamber allows you to shoot either round too but the chamber is larger and through the sizing it works the brass more. I couldn't see any advantage for the Wylde chamber over the 556 chamber.
Essentially the Wylde chamber is fatter to make up for the short free bore. Instead of the bullet moving freely toward the rifling through the free bore the Wylde chamber allows the brass to expand in the chamber. They both reduce the pressures. Since the brass is worked less in the 556 chamber I chose it.

JasonKramer · February 22, 2017, 03:52 PM

I would recommend taking a two stage bore brush with your power drill. Pay particular attention to the lead and make sure that it is free from any burs or blemishes. Second step would be to ensure that there is no sharp edges on the feed ramps. These edges could mar the brass and create an issue for the extractor. The feed ramps can be polished with buffing/finishing compound. If you are not confident in your abilities please take it to a local gunsmith. They will be able to complete the fine adjustments to your feed ramps/chamber/and lead. Second culprit, check your gas system assembly for proper alignment. Some gas being present on the barrel around the gas block isn't necessarily a problem but if it is excessive it may indicate an alignment issue, gas port blockage, or gas tube issue. If your extractor is deforming the rim or head it would indicate that there is an issue with the extractor but the chances of that are far less likely than the other problems I have mentioned.

Mobuck · February 24, 2017, 07:56 AM

"The primary reason you don't see oilers on post WW2 firearms is because of fluted chambers. Instead of oil breaking the friction between case and chamber, high pressure gas breaks the friction. If bolt thrust is bad, then fluted chambers are bad."

The difference comes from the ORIGINAL DESIGN. If the firearm was DESIGNED (or re-designed) to use lubed cases or a fluted chamber this is very different compared to using lubed cases in a fire arm DESIGNED to operate with un-lubed cases. I would also not use ANY military design as an absolute baseline since many military designs/re-designs were expedients in the face of war needs and not entirely safe in the long term and/or simply a way to put un-serviceable or poorly designed guns back in action.
Do as you darned well please and so will I. I will say that the need for lubing cases (in an AR platform) can only be considered a cover up of some other problem.

Slamfire · February 24, 2017, 08:31 AM

Quote:

The difference comes from the ORIGINAL DESIGN. If the firearm was DESIGNED (or re-designed) to use lubed cases or a fluted chamber this is very different compared to using lubed cases in a fire arm DESIGNED to operate with un-lubed cases

What loads are firearms designed to hold? No firearm structure is weakened assuming that the case carries any load.

Are you aware that aluminum cases are coated with a wax, which is there to act as a lubricant, to break the friction between case and chamber, so the cases won't stick in the chamber? This is per George Frost "Making Ammunition".

What about those steel cases coated in teflon? It is called a polymer, because the manufacturer's know if they told you the coating is a rust preventative and lubricant, they would be spending all their time explaining why these cases are safe to use.

What about friction reducing coatings such as nickel cases? Making the case slicker reduces friction. How does that fit into your original design idea?. What about chrome plating the chamber. You know the original AR's did not have a chrome plated chamber, then, it was implemented as a rust prevention and friction breaking measures.

What about the chamber flutes that current manufacturer's are using in AR15's?. Those were not in the original design and yet those AR's use standard bolts.

Why do you want to stress the weakest part of the mechanism? The cartridge case is far weaker than the steel components of the locking mechanism and barrel, and yet, you want to stress the cartridge case. Do you think the case is strong and the action is weak? Why do you want to increase the chance that the case will fail, by making it carry load?

Mobuck · February 24, 2017, 01:54 PM

"Are you aware that aluminum cases are coated with a wax, which is there to act as a lubricant, to break the friction between case and chamber, so the cases won't stick in the chamber? This is per George Frost "Making Ammunition"."

I'm aware that aluminum cases are most often used for handgun ammo.

"What about those steel cases coated in teflon? It is called a polymer, because the manufacturer's know if they told you the coating is a rust preventative and lubricant, "

Steel cases are "coated" because they don't "spring back" as brass does to relieve the friction between case and chamber.

"You know the original AR's did not have a chrome plated chamber, then, it was implemented as a rust prevention"

Do you disagree that this qualifies as a "design/re-design of the firearm" and IIRC was an attempt to overcome fouling build-up(in combat conditions) causing failure to extract.

Slamfire · February 24, 2017, 07:16 PM

Quote:

Do you disagree that this qualifies as a "design/re-design of the firearm" and IIRC was an attempt to overcome fouling build-up(in combat conditions) causing failure to extract.

At some point, breech friction will disable any semi auto and manual firearm. It behooves the user to keep their firearm clean, rust free, and well oiled. What techniques I did list did not change the structural load path, pressure curve, nor the timing, of any firearm. They all did reduce breech friction. Some by making the chamber slicker, others by making the ammunition slicker.

The basic fact of the matter is, as long as the shooter uses ammunition whose pressure is within the boundaries set by the designer, lubricating cases will not damage the firearm. What will damage the firearm, reduce its life expediencies, damage the cases, are pressures above design specifications. For civilians reloading for their own firearms, keeping pressures at or below SAAMI specifications is the smartest, safest thing they can do. For old firearms, SAAMI has taken a best guess at safe pressures, and for new cartridges and firearms, the designers and the ammunition makers can collaborate so the ammunition pressure limits set by SAAMI will at least be based on the structural limits of the firearms.

No one ever has, or ever will, weaken their locking mechanism based on the assumption that the cartridge case carries any load. Therefore, as long as pressures are within SAAMI limits, oiled cases and chambers will not damage the firearm.

This history of this coverup goes back at least a century when the US Army built 1,000,000 structurally defective M1903's. The Army never owned up to their defective rifles, created myths and produced out right lies to cover up blow ups caused by defectively built rifles. What is more, the Army issued these rifles to Troops knowing that 33 1/3% of them would fail catastrophically in an over pressure situation. The shooting public embraced these falsehoods and what is more amazing, is these so called experts in Gun Magazines and Reloading Manuals never, ever, ever, figured out that what they were preaching, was an Army lie.

Mobuck · February 25, 2017, 08:25 AM

Slamfire,
Are you claiming that the force applied by a fired cartridge against the bolt face has no bearing on firearms design?

HiBC · February 25, 2017, 08:27 AM

Slamfire,I'm all for you being free to think as you think,believe what you believe,and lube or not lube your ammo as you see fit.

I'm not interested in even trying to change your mind. Relax,live in peace.

I'd like for you to extend to folks who prefer dry ammo the same courtesy.

I could be wrong,but it seems I read the problem with either the 1903's or the Eddystones had to do with some new manager at the arsenal ordering all the dingy windows cleaned.This changed the ambient light in the shop.That caused problems because the heat treating in those days was controlled by the experience eyes of the heat treater. The brighter ambiance led to over heating the steel.

Something else I could be wrong about,it seems I recall reading that the delayed blowback roller lock rifles like the CETME initially had case failures with unfluted chambers. That may have been aggravated by a NATO ammo requirement. I don't know for sure,I can't document it, but I think the fluted chamber was a fix ,or "evolution" to make the design work.

Stoner's original AR design did have a chrome chamber. Our DOD wizards decided to eliminate the chrome chambers,AND use 7.62 powder to boot.
Bean counters, and some good people paid a higher price than the beancounters saved.

Testimony that disagrees with your beliefs can be found in PO Ackley's experiments with removing the locking bars from a Win 94. Whether you agree or whether itsall valid , PO did conduct the experiments . There are two sides to the argument.
I,too,have the freedom to choose what I believe.

I'm also quite sure that lube collects dirt. Sand,etc. It deposits in the weapon.Lube,sand,etc.

Now,black powder folks are quite aware lubrication of the bullet or ball is important with black powder.They are also quite aware that the lubes of choice are animal or vegetable,not petro.(with some exceptions,like Vaseline)

Why is that? What do they make blacktop roads out of? Oil and sand that has been heated. It makes asphalt.

You go right ahead and do it your way.Enjoy!!

I'll do it mine!! Dry ammo!

We can both be happy.

ed308 · February 26, 2017, 11:44 AM

MagnoliaHunter, did you resolve the problems your were having? I would check to see if you gas block has shifted, replace the extractor spring (cheap) and clean/polish the chamber. And run the AR wet. If you've got a A2 front sight post with gas block, you can probably skip that one since they are usually pinned. But look closely at any gas block that is attached with screws. You Tube is your friend for checking and doing the above.

I've read a lot of post lately where extractor springs are bad and not lasting. I'm getting ready to replace one on my 270AR that started having similar problems when I hit 200+ rounds. But since I'm using my reloads I'll also check how far back I'm bumping the shoulder on my brass which can also cause stuck cases. I've certainly perfected mortaring an AR with my 270AR!

February 20, 2017, 08:47 AM	#30
stagpanther Senior Member Join Date: March 2, 2014 Posts: 11,789	If fluted chambers really add to reliability--why aren't more manufacturers using them? http://www.thefirearmblog.com/blog/2...uted-chambers/ __________________ "Everyone speaks gun."--Robert O'Neill *I am NOT an expert--I do not have any formal experience or certification in firearms use or testing; use any information I post at your own risk!*

February 20, 2017, 10:09 AM	#33
stagpanther Senior Member Join Date: March 2, 2014 Posts: 11,789	I'm not an expert--in fact, I usually claim to be the opposite--closer to the "have no clue" camp. ; ) But I do try to reason things out on my own. Based on my limited experience, any scheme for "unlocking" a case from a chamber is essentially a device for correcting a "asymmetry" between the case contraction upon firing and the automatic bolt extraction. This "asymmetry" I believe can exist for different reasons in my experience, but the net result is the same--a "sticky" case. I believe that's why most commercial barrels tend to be over-gassed, but that's just a guess on my part. I can see why a fluted chamber might make sense for a "life or death must fire" combat weapon--but I just haven't heard of this being used widely--especially on precision rifles, and in that sector of the market I would guess cost is irrelevant if it could produce even a 1/1000th MOA improvement. Your middle picture with the cases in hand--when I see a case like that with a gas ring forward of the neck it usually indicates a problem with chambering/headspacing in my AR's--but maybe that's just some weirdness you get with the gas blowback. __________________ "Everyone speaks gun."--Robert O'Neill *I am NOT an expert--I do not have any formal experience or certification in firearms use or testing; use any information I post at your own risk!* Last edited by stagpanther; February 20, 2017 at 10:15 AM.

February 21, 2017, 09:18 AM	#38
ed308 Senior Member Join Date: November 5, 2016 Location: DFW, TX Posts: 1,147	5.56 Nato is larger in the free bore diameter. The .223 Remington is .2240. 5.56 Nato is .2265 and .223 Wylde is .2242. Bill Wylde developed his chamber to exploit the better accuracy of the .223 Remington chamber but without the pressure problems encountered when shooting 5.56 Nato ammo in a .223 Remington chamber barrel. The tighter .2240 free bore diameter really helps for tighter groups. And the .223 Wylde chamber likes longer and heavier bullets. Here's a link to Pacific Tool and Gauge chamber prints: http://http://www.practicalmachinist...e-chambers.jpg Last edited by ed308; February 21, 2017 at 09:28 AM.

February 22, 2017, 03:52 PM	#43
JasonKramer Junior Member Join Date: February 22, 2017 Posts: 1	The truth is somewhere in the middle... I would recommend taking a two stage bore brush with your power drill. Pay particular attention to the lead and make sure that it is free from any burs or blemishes. Second step would be to ensure that there is no sharp edges on the feed ramps. These edges could mar the brass and create an issue for the extractor. The feed ramps can be polished with buffing/finishing compound. If you are not confident in your abilities please take it to a local gunsmith. They will be able to complete the fine adjustments to your feed ramps/chamber/and lead. Second culprit, check your gas system assembly for proper alignment. Some gas being present on the barrel around the gas block isn't necessarily a problem but if it is excessive it may indicate an alignment issue, gas port blockage, or gas tube issue. If your extractor is deforming the rim or head it would indicate that there is an issue with the extractor but the chances of that are far less likely than the other problems I have mentioned.

February 19, 2017, 04:18 PM	#26
ShootistPRS Senior Member Join Date: January 3, 2017 Posts: 1,583	I have to comment on two pieces of information that have been made as they conflict with facts as I know them. 1. Wylde chambers: Wylde chambers are larger than the 223/556 chambers. The length of a SAAMI 223/556 chamber is 1.760 from base to mouth while the Wylde chamber is at least 1.773 (minimum). The SAAMI diameter of the shoulder to body junction is .354 for 223/556 while the Wylde chamber is .3572 The chamber mouth diameter for SAAMI chamber is .253, the Wylde chamber mouth is .2558; The Wylde chamber was designed so the 223/556 cartridges could be fired interchangeably without considerations for free bore which is the difference in the chambers of 223 and 556. On chamber lube: 2. Every reloading book and manual I have read in the past 45 years state that oiling a chamber or cartridge increases the back thrust on the bolt and for that reason it is imperative that chambers and cases be clean and dry when loading. If anyone can point to a reputable article that states otherwise I would be happy to see it. These two items are not intended to start arguments, rather to put out factual information to those who are new to reloading and the AR platform and its different attributes. I steered away from the Wylde chamber simply because it would cause the cartridge to expand more when fired and therefore worked more when resized causing earlier failure of the cases.

February 19, 2017, 05:40 PM	#27
ed308 Senior Member Join Date: November 5, 2016 Location: DFW, TX Posts: 1,147	Hmm..., I always thought 5.56 NATO chamber has a longer throat compared to the .223 chamber so it can handle the higher pressure produced by the 5.56 NATO round. With that said, .223 is usually the more accurate than 5.56 NATO. The Wylde chamber was designed to gain the accuracy advantages of the .223 Remington but also allow you to safely shoot 5.56 NATO without the pressure problems associated with .223. To each his own, but the Wylde is the best of both worlds IMO. But I also like to shoot the heavier bullets in my Wylde chamber barrels. And they are more accurate than my 5.56 barrels.

February 19, 2017, 06:04 PM	#28
ShootistPRS Senior Member Join Date: January 3, 2017 Posts: 1,583	ED, The throat of the 556 is longer than the 223 - that is the free bore part of the chamber. The chamber length is the distance from the bolt face to the mouth of the cartridge and the head space is the length from the bolt face to the distance to the datum of the shoulder. The Wylde camber has more head space while the 223 and 556 share the same, shorter, head space. As far as accuracy goes there are a lot more variables and the barrel leade and quality have more to do with it than the chamber does (IMHO). There is also the point that the Wylde chamber is not specified by SAAMI so it can vary a lot more than the SAAMI standard chambers. The dimensions for the Wylde chamber that I have are from a Reamer drawing from Manson Precision Reamers. They agree with other dimensions that I have seen but this is the only one I have in my records.

February 20, 2017, 01:30 PM	#36
ShootistPRS Senior Member Join Date: January 3, 2017 Posts: 1,583	The model 91 and 93 from H&K have fluted chambers, hex rifling and a delayed blow back operating system. Each part works with the others to provide a smooth functioning firearm. The fluted chambers are self cleaning because of the gas flow through the chamber when the bolt begins to open. The hex rifling allows higher velocities than standard styles of cut, hammered and button rifling. The fluted chamber lowers the amount of force it takes to extract the case and the blow-back operation is timed to operate after the pressure has dropped to a safe level. The gas that flows around the case is also used to flush any debris out of the chamber to keep the gun operating in poor conditions. It is, after all, a military firearm. It is just one way to keep a military rifle operational in adverse conditions. It is not the only way.

February 21, 2017, 11:53 AM	#39
2damnold4this Senior Member Join Date: August 12, 2009 Location: Athens, Georgia Posts: 2,526	I took it for granted that the Wylde chamber was tighter in most ways than the 5.56 and as ShootistPRS has pointed out, the Wylde chamber is larger with a few exceptions.

February 21, 2017, 06:51 PM	#40
ShootistPRS Senior Member Join Date: January 3, 2017 Posts: 1,583	When I decided I needed a semi auto rifle for three gun I did a lot of research. The Wylde chamber was one that I originally had wrong too. From all the descriptions and that it was based on getting more accuracy, like many, I thought it was a tighter chamber. I found a reamer print for it and compared it to the SAAMI prints and decided it was not for me unless I was willing to get dies specifically made for that chambering. I eventually opted to get the 556 chamber. I can't say whether my decision was right or not because, although I have had my gun for two weeks, I have not been able to shoot it yet! (it is really messing with my mind to have a new gun and lots of ammo sitting around the house and no way to use it) If anyone knows of a burglar, who wants to die a horrible death at the hands of a frustrated AR owner, you can send him my way.

February 21, 2017, 09:34 PM	#41
ed308 Senior Member Join Date: November 5, 2016 Location: DFW, TX Posts: 1,147	ShootistPRS, what was thinking for the Nato chamber and 3 Gun? 5.56 Nato probably is the best choice for 3 Gun if using a lot of different ammo. I use a lot of different ARs for 3 Gun depending on what the course is. I'll even pull out one of my 6.8s on occasion. I did build a 18" .223 Wylde AR specifically for 3 Gun and which I run most of the time. I went with the Wylde chamber for the accuracy and reliability. I shoot a lot of Nosler 69 and 77 gr Custom Comp (HPBT) bullets and they shoot 1/2" groups in my AR15 Performance 223 Wylde barrels. They proven to be accurate and reliable for me through the years. I did take a chance a couple of weekends ago and tried Tula Steel case 77 gr HPBT just to see how they would do. I figure I would get a stuck but they ran fine. Same for my pistol too. It was kinda nice not to have to find my brass. But my FNH SLP shotgun did malfunction and for the first time I got stuck in the chamber and had to mortar it in the middle of the course. I've never mortar a shotgun in my life either LOL! It'll get a good cleaning the match next month.

February 22, 2017, 03:01 PM	#42
ShootistPRS Senior Member Join Date: January 3, 2017 Posts: 1,583	Ed, My thinking was that of using a tight chamber to work the brass less. I could have used the 223 or 556 chamber because the chamber dimensions are the same. You shouldn't use 556 ammo in the 223 camber because it has less free bore. I chose the 556 chamber so I can fire either brass equally well. The Wylde chamber allows you to shoot either round too but the chamber is larger and through the sizing it works the brass more. I couldn't see any advantage for the Wylde chamber over the 556 chamber. Essentially the Wylde chamber is fatter to make up for the short free bore. Instead of the bullet moving freely toward the rifling through the free bore the Wylde chamber allows the brass to expand in the chamber. They both reduce the pressures. Since the brass is worked less in the 556 chamber I chose it.

February 24, 2017, 07:56 AM	#44
Mobuck Junior member Join Date: February 2, 2010 Posts: 6,846	"The primary reason you don't see oilers on post WW2 firearms is because of fluted chambers. Instead of oil breaking the friction between case and chamber, high pressure gas breaks the friction. If bolt thrust is bad, then fluted chambers are bad." The difference comes from the ORIGINAL DESIGN. If the firearm was DESIGNED (or re-designed) to use lubed cases or a fluted chamber this is very different compared to using lubed cases in a fire arm DESIGNED to operate with un-lubed cases. I would also not use ANY military design as an absolute baseline since many military designs/re-designs were expedients in the face of war needs and not entirely safe in the long term and/or simply a way to put un-serviceable or poorly designed guns back in action. Do as you darned well please and so will I. I will say that the need for lubing cases (in an AR platform) can only be considered a cover up of some other problem.

February 24, 2017, 01:54 PM	#46
Mobuck Junior member Join Date: February 2, 2010 Posts: 6,846	"Are you aware that aluminum cases are coated with a wax, which is there to act as a lubricant, to break the friction between case and chamber, so the cases won't stick in the chamber? This is per George Frost "Making Ammunition"." I'm aware that aluminum cases are most often used for handgun ammo. "What about those steel cases coated in teflon? It is called a polymer, because the manufacturer's know if they told you the coating is a rust preventative and lubricant, " Steel cases are "coated" because they don't "spring back" as brass does to relieve the friction between case and chamber. "You know the original AR's did not have a chrome plated chamber, then, it was implemented as a rust prevention" Do you disagree that this qualifies as a "design/re-design of the firearm" and IIRC was an attempt to overcome fouling build-up(in combat conditions) causing failure to extract.

February 25, 2017, 08:25 AM	#48
Mobuck Junior member Join Date: February 2, 2010 Posts: 6,846	Slamfire, Are you claiming that the force applied by a fired cartridge against the bolt face has no bearing on firearms design?

February 25, 2017, 08:27 AM	#49
HiBC Senior Member Join Date: November 13, 2006 Posts: 8,288	Slamfire,I'm all for you being free to think as you think,believe what you believe,and lube or not lube your ammo as you see fit. I'm not interested in even trying to change your mind. Relax,live in peace. I'd like for you to extend to folks who prefer dry ammo the same courtesy. I could be wrong,but it seems I read the problem with either the 1903's or the Eddystones had to do with some new manager at the arsenal ordering all the dingy windows cleaned.This changed the ambient light in the shop.That caused problems because the heat treating in those days was controlled by the experience eyes of the heat treater. The brighter ambiance led to over heating the steel. Something else I could be wrong about,it seems I recall reading that the delayed blowback roller lock rifles like the CETME initially had case failures with unfluted chambers. That may have been aggravated by a NATO ammo requirement. I don't know for sure,I can't document it, but I think the fluted chamber was a fix ,or "evolution" to make the design work. Stoner's original AR design did have a chrome chamber. Our DOD wizards decided to eliminate the chrome chambers,AND use 7.62 powder to boot. Bean counters, and some good people paid a higher price than the beancounters saved. Testimony that disagrees with your beliefs can be found in PO Ackley's experiments with removing the locking bars from a Win 94. Whether you agree or whether itsall valid , PO did conduct the experiments . There are two sides to the argument. I,too,have the freedom to choose what I believe. I'm also quite sure that lube collects dirt. Sand,etc. It deposits in the weapon.Lube,sand,etc. Now,black powder folks are quite aware lubrication of the bullet or ball is important with black powder.They are also quite aware that the lubes of choice are animal or vegetable,not petro.(with some exceptions,like Vaseline) Why is that? What do they make blacktop roads out of? Oil and sand that has been heated. It makes asphalt. You go right ahead and do it your way.Enjoy!! I'll do it mine!! Dry ammo! We can both be happy.

February 26, 2017, 11:44 AM	#50
ed308 Senior Member Join Date: November 5, 2016 Location: DFW, TX Posts: 1,147	MagnoliaHunter, did you resolve the problems your were having? I would check to see if you gas block has shifted, replace the extractor spring (cheap) and clean/polish the chamber. And run the AR wet. If you've got a A2 front sight post with gas block, you can probably skip that one since they are usually pinned. But look closely at any gas block that is attached with screws. You Tube is your friend for checking and doing the above. I've read a lot of post lately where extractor springs are bad and not lasting. I'm getting ready to replace one on my 270AR that started having similar problems when I hit 200+ rounds. But since I'm using my reloads I'll also check how far back I'm bumping the shoulder on my brass which can also cause stuck cases. I've certainly perfected mortaring an AR with my 270AR!