CLE match AR15 chamber issues and questions

[Dev L]

So I purchased a full custom Bartlein 1/7.7 CLE match chambered barrel as part of a lightweight precision build. While this used to be advertised as a 5.56 match chamber it is clearly a .223 chamber due to the very short freebore. It shoots anything at .233 pressure well. It shoots crap Freedom Munition .223 55 grain FMJ 1.5 MOA. It shoots .223 77 Gold Medal Match about .7-.8 MOA. It shoots both 5.56 Black Hills 77 TMK and 5.56 American Eagle 55 FMJ 3.0 MOA. With 5.56 75 grain Hornady or 5.56 Black Hills it has big burs on the back of the brass from the ejector you can see and feel. Primers are pretty flattened. 5.56 75 grain Frontier feels like it sticks bullets on the lands just a but so extracting a chambered but unfired round is difficult.

My question is... over time, as the throat wears, will it be able to shoot 5.56 loads one day, or is it always going to require .223 ammo?

I was really hoping to hit 2700 FPS with factory Black Hills 77 TMK, but wonder if that will even be possible with handloads. Does anyone have any experience with the CLE chamber?

I got a Krieger 1/7 223 Wylde in case this barrel does not work out, but was hoping the Bartlein would hold its own for this weight conscious precision build. Both barrels are 16" and will be shot suppressed. The CLE is .775 fluted under the handguards and 29.8oz. The Krieger is .850 under handguards unfluted and 34oz. The Bartlein does just over 2700 with no silencer with factory Black Hills 5.56 77 TMK, but it has horrible vertical strings that are not caused by velocity.

 

[bigjake83]

So I purchased a full custom Bartlein 1/7.7 CLE match chambered barrel as part of a lightweight precision build. While this used to be advertised as a 5.56 match chamber it is clearly a .223

The CLE Match Chamber is .223 ONLY! And has never been advertise as anything else.

 

[lennyo3034]

For my Krieger with CLE match chamber:

I’m loading the 77tmk over 22.6 grains of 8208. Well under max and the rifle runs nicely. 2720 with it.

Same rifle with factory IMI 77 is 2900.

 

[mheimer_45]

The CLE Match Chamber is .223 ONLY! And has never been advertise as anything else.

Well this is new. When I ordered my Douglas from them in January, Paul at CLE advised me I could shoot either 5.56 or .223 threw my CLE chamber. I also remember an email from Theresa saying it was also ok for 5.56 ammo.

 

[mheimer_45]

 

[bigjake83]

View attachment 7079883

I'm sure they were talking about "their Wylde Chamber" nowhere in that email does it State what chamber offering of theirs you two are discussing.

I would give them a call on Monday or send another email for more clarification. If you can get confirmation that the CLE match chamber is NOT specifically designed for .223 I will be happy to admit that I'm wrong, but I don't think I am.

 

[mheimer_45]

And I do remember talking to Paul a second time and asking him the same question.

 

[bigjake83]

View attachment 7079887
And I do remember talking to Paul a second time and asking him the same question.

I've personally had over 20 barrels made for me over the years by Frank, and I have not once been told it's ok to shoot NATO ammo from the CLE Match Chamber.

Because the Wylde chamber is essentially the closest you're going to get to a" 5.56 Match Chamber".

This to me is very odd, and according to the above emails I AM WRONG but it still feels like something's amiss.

I wish padam was hanging around somewhere he might know more than both of us, either way I'm personally going to email CLE Monday and get clarification because this is quite interesting.

 

[mheimer_45]

Well to be honest I’m just using what I’ve been told. It’s the whole reason I went CLE chamber. And the barrel is still sitting in the damn box from CLE. Not yet mounted. I was going to send it back to CLE for a thread job after I bought my suppressor but time and work got in the way. I will also speak with them before I send it in and if I was told the wrong info maybe they will rechamber it for me.

 

[MontanaMan]

Some interesting comments in this thread; be interested to hear what get posted after more conversations with CLE.

Here's some chamber/reamer info that I found; some interesting info here that kinda contradicts some of what I thought I knew....................

MM

 

[bigjake83]

Where the hell is Padom!..lol

 

[MontanaMan]

Yeah, I haven't seen him around much lately.

MM

 

[whatsupdoc]

From the CLE Site.

---------------------------------------------------------------
Match competitors usually choose the CLE chamber.

The CLE match chamber is basically the same as a .223 SAAMI spec chamber with a modified lead angle in the throat. The CLE chamber has a 1.5 degree lead angle per side where the .223 is over 3 degrees. This allows for less bullet jump with out of the magazine ammo yet still providing an advantageous lead angle for modern high ballistic coefficient bullets. The Wylde chamber is .002 bigger in the cartridge case area and has a longer throat. On the average the CLE chamber will shoot 23% smaller groups with out of the magazine ammo. The CLE match chamber will give better barrel life due to the shorter throat and gives slightly higher pressure.

There has been no problem shooting PMC, Lake City and IMI .556 Rounds out of the CLE chamber.

It is ultimately up to the shooter to determine the suitability of the ammo in a particular firearm.

Here is a chamber ream comparison chart. Click Here

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"It is ultimately up to the shooter to determine the suitability of the ammo in a particular firearm"

So this tells me that although CLE did not have issues with 5.56 in their testing there maybe issues with some firearms.
I have a CLE chamber spec kreiger barrel (not done by compass lake) that I use 5.56 ammo in with out any issue. I have used the hornady frontier 75gr 5.56 and the bullets were jammed into the lands so I stopped using them even though they shot 3/4 moa without any issue except as above hard extraction of a live round.

I was getting some extractor damage on the case rims so I replaced 3 of the 5 steel weights with 3 tungsten weights on a rifle length buffer and it stopped.

I currently use magtec 77gr in my CLE chamber and it runs perfectly, have used the FC262 77gr and the federal 62gr otm without issue.
YMMV

 

[MontanaMan]

From the CLE Site.

---------------------------------------------------------------
Match competitors usually choose the CLE chamber.

The CLE match chamber is basically the same as a .223 SAAMI spec chamber with a modified lead angle in the throat. The CLE chamber has a 1.5 degree lead angle per side where the .223 is over 3 degrees. This allows for less bullet jump with out of the magazine ammo yet still providing an advantageous lead angle for modern high ballistic coefficient bullets. The Wylde chamber is .002 bigger in the cartridge case area and has a longer throat. On the average the CLE chamber will shoot 23% smaller groups with out of the magazine ammo. The CLE match chamber will give better barrel life due to the shorter throat and gives slightly higher pressure.

There has been no problem shooting PMC, Lake City and IMI .556 Rounds out of the CLE chamber.

It is ultimately up to the shooter to determine the suitability of the ammo in a particular firearm.

Here is a chamber ream comparison chart. Click Here

----------------------------------------------------------------

"It is ultimately up to the shooter to determine the suitability of the ammo in a particular firearm"

So this tells me that although CLE did not have issues with 5.56 in their testing there maybe issues with some firearms.
I have a CLE chamber spec kreiger barrel (not done by compass lake) that I use 5.56 ammo in with out any issue. I have used the hornady frontier 75gr 5.56 and the bullets were jammed into the lands so I stopped using them even though they shot 3/4 moa without any issue except as above hard extraction of a live round.

I was getting some extractor damage on the case rims so I replaced 3 of the 5 steel weights with 3 tungsten weights on a rifle length buffer and it stopped.

I currently use magtec 77gr in my CLE chamber and it runs perfectly, have used the FC262 77gr and the federal 62gr otm without issue.
YMMV

That's the same chart that I posted; there's some interesting info there.....................draw your own conclusions.

That's why pressure is pressure & the chronograph is your friend.

MM

 

[bigjake83]

I'm just going to keep it simple and keep advising people the same way. If you want to run NATO and .223 get the Wylde chamber if not use the CLE Match chamber. To be completely honest I can't tell a difference in accuracy with my 77gr SMK Handloads or Black hills 77gr ammo, but I also only run the 1-7.7 twist Bartlein or Kriegers. It's unfortunate that Mheimer is running into some complications with certain loads I'm sure it's frustrating.

Its awesome Mheimer brought some of this to our attention I think we've all learned a little something new from this thread.

 

[Dev L]

So it sounds like I should be able to get a handload where I want velocity wise. Still, will it be able to shoot 5.56 Black Hilks factory ammo eventually, as it wears and the bullet jump to lands increases? If so, how many rounds till it gets there?

 

[whatsupdoc]

So it sounds like I should be able to get a handload where I want velocity wise. Still, will it be able to shoot 5.56 Black Hilks factory ammo eventually, as it wears and the bullet jump to lands increases? If so, how many rounds till it gets there?

Forget the throat erosion!
Waiting for the throat to erode to use a particular round is well crazy. I checked the erosion after 900 rounds and could not measure a difference from when i checked it new.

You should be able to find factory 5.56 round that works and use it. I would do another CLE in a second just need to find what works with it.

 

[mheimer_45]

I'm just going to keep it simple and keep advising people the same way. If you want to run NATO and .223 get the Wylde chamber if not use the CLE Match chamber. To be completely honest I can't tell a difference in accuracy with my 77gr SMK Handloads or Black hills 77gr ammo, but I also only run the 1-7.7 twist Bartlein or Kriegers. It's unfortunate that Mheimer is running into some complications with certain loads I'm sure it's frustrating.

Its awesome Mheimer brought some of this to our attention I think we've all learned a little something new from this thread.

It’s not me having problems. I still haven’t found time to get my barrel mounted. I just know that I went CLE chamber because I was told it would shoot both.

 

[bigjake83]

It’s not me having problems. I still haven’t found time to get my barrel mounted. I just know that I went CLE chamber because I was told it would shoot both.

Oh.. sorry

Either way very informative thread, thanks to all for help working this out.

 

[USMC_JA]

As a further data point, that is likely not needed at this juncture, Paul also told me 556 ammo is perfectly fine in the CLE chamber. And I ordered my barrel Bartlein 1:7.7 in January of this year.

 

[lennyo3034]

FWIW, I’ve popped primers with IMI 77 in the CLE chamber but not the wylde.

 

[Laseredge]

FWIW, I’ve popped primers with IMI 77 in the CLE chamber but not the wylde.

Same here on the IMI 77, but the Black Hills 5.56 77 with crimped primers is 100%.

 

[whatsupdoc]

FWIW, I’ve popped primers with IMI 77 in the CLE chamber but not the wylde.

That is not uncommon, the military has done studies to try and find the cause of "dropped primers" in 5.56 ammo.

I had some German 62gr ammo stamped .223 / 5.56 on the case head. I was waiting for my jp bolt to arrive but being impatient I threw in a off brand NiB bolt carrier group and went to the range.
Every one of the 223 / 5.56 stamped rounds popped the primer. The other ammo I had brought along had no such issue.

Later I installed the JP bolt using a colt bolt carrier and tested the same 223 / 5.56 ammo, no more popped primers.
I measured the fired cases and found that the brass fired with the JP bolt were .001 longer than with the NiB bolt. This gave me .001 longer head space which seems to have made the difference between the primers popping or not.
Finicky little thing but she will hit a 12 plate at 805 like nobody's business.