.223 case seperation

[MGYSGT]

Shot a Mid Range match in 29 Palms this past weekend. Had 3 cartridge failures with new LC brass (LC11). 80 gr Hornady and 24 gr Varget. About 1/3 up the case the cartridge came out of the chamber with the dreaded black ring. When I applied pressure the cartridge snapped in half. Guess I am lucky it didn't stay in the chamber. I have shot 1500 rounds out of this rifle and never had this happen prior to Saturday. What could have changed to cause this? Brass, Headspace, Loading voodoo?

Tom

 

[DukeDuke]

your brass must have been tired.

 

[jonbearman]

Did you weigh each charge,did you work up to that load inyour rifle? How do you size as you can and will induce headspace issues if you oversize.Are you setting the die to touch the shellholder or are you montioring the shoulder setback?

 

[jpretle]

You might consider checking your sized head-space as opposed to head-space as they come out of the chamber.
A head-space gauge goes a long way to saving a lot of headaches.

 

[Rick in Oregon]

A head-space gauge goes a long way to saving a lot of headaches.

Yesir it does! I'm alot happier now that I'm using the Stoney Point set of headspace guages, purchased from Sinclair. You can keep track of shoulder movement and prevent hard bolt closing or "other" mishaps. Valuable piece of gear.

 

[Turbulent Turtle]

Shot a Mid Range match in 29 Palms this past weekend. Had 3 cartridge failures with new LC brass (LC11). 80 gr Hornady and 24 gr Varget. About 1/3 up the case the cartridge came out of the chamber with the dreaded black ring. When I applied pressure the cartridge snapped in half. Guess I am lucky it didn't stay in the chamber. I have shot 1500 rounds out of this rifle and never had this happen prior to Saturday. What could have changed to cause this? Brass, Headspace, Loading voodoo?

Tom

What preparations do you perform on virgin brass before the first firing? Do you just prime, load powder and seat bullet or do you do more work?

 

[Beau]

Is it the LC1 that several vendors were selling as new, unfired brass? Heard there's been some problems with that brass.

Sounds like a pretty typical failure on reloaded 223 cases. Just remember to keep your sizing die set for 3 thou shoulder set back to minimize (but not totally eliminate) this problem.

 

[bigedp51]

Two things that help prevent case head separations.

Measuring the fired length of your case, below.

And the correct shoulder bump when sizing, below .003 for my AR15 rifles.

The above gauge has been adjusted to give actual chamber headspace readings.

I use the RCBS Case Mastering Gauge to check for case wall thinning in the base web area of the case. This is far more accurate than a bent paper clip and gives readings in thousandths of an inch.

In over 46 years of reloading I have never had a case head separation, through careful case inspections and minimum shoulder bump. Even when collecting and shooting .303 British rifles which are notorious for case head separations.

 

[pdhntr]

.... About 1/3 up the case...

Tom,

This sounds like it is above the web where a typical CHS takes place. Is that accurate?

Jim

 

[bigedp51]

MGYSGT

You stated you are using "NEW" Lake City brass..............

Do you have a friend at Lake City giving you brand new unfired cases : or do you mean once fired Lake City cases.

Federal is loading 5.56 ammunition with LC cases that are rejects and did not meet milspec standards.

If you have once fired LC brass that was fired in a machine gun the case will stretch badly when fired in the machine guns "LARGER DIAMETER" and much "LONGER" headspaced chamber settings. (NO-GO for a M249 is 1.4982 and NO-GO for the M16/A4 is 1.4706 plus the M249 chamber is .003 larger in diameter)

What do you mean by "new LC brass"

 

[LRPV]

Midway and I would assume some other companies have sold NEW never loaded Lake City headstamped brass in the past. I bought some LC11 a couple or 3 years ago. They were not previously fired.

 

[bigedp51]

Midway and I would assume some other companies have sold NEW never loaded Lake City headstamped brass in the past. I bought some LC11 a couple or 3 years ago. They were not previously fired.

These cases being sold by Midway and others are Lake City seconds, rejects or whatever you wish to call them. All these cases FAILED milspec requirements and Lake City refused to use them and then sold them off to the highest bidder as scrap brass.

I have been sorting Lake City cases loaded by Federal for weeks and they do not meet the milspec standards for dimensions you see below. They fail the required case wall thicknesses and neck thickness requirements. They fail prime pocket dimensions and I think many fail hardness requirements.

Bottom line, what many of us have are Lake City rejects and the military loads the cases that passed inspection requirements for their good ammunition.

Do you actually think the ammo below was loaded at Lake City and sold to the civilian market?

These cases above are military rejects and nothing more.

 

[DR1586]

Biged,

I'll send you my address, you just go ahead and send me all the cases that fail the wall thickness and other tests, I'll take care of them.

 

[pdhntr]

The reason I asked Tom about where the cases let go is because I have a NEW batch of LC10, and had several let go above the web when shot for the first time in my AR.

What I mean by NEW is never fired.

Jim

 

[bigedp51]

Biged,

I'll send you my address, you just go ahead and send me all the cases that fail the wall thickness and other tests, I'll take care of them.

Sounds great, all the Lake City once fired cases below have oversized primer pockets and you can seat the primers with your finger.

I'm sorting through three five gallon buckets of .223/5.56 once fired brass looking for cases worthy of sorting by weight, and prepping for shooting from a A2 HBAR and a 26 inch heavy barrel .223 rifle. I use the rejected cases for blasting and practice ammo in my AR15 carbine.

 

[MGYSGT]

My cases are "New" unfired LC-11. I do turn the necks slightly to uniform them prior to fire-forming them. I do not know if they are rejects or not. I shot them in my Savage Target action not an AR. I will check all those suggestions you have given me. Thank you

Tom

 

[infantrytrophy]

Do your case separations look like this (at the top of the picture)?

If yes, then your problem is either the headspace of your rifle or a problem with the brass (case head to shoulder distance too short - new brass out of spec or fired brass sized back to much).

Notice the thinned "ring" in the inside wall of the brass. This is where the brass stretched when fired. Too much of this stretch results in the separation, as seen in the piece of brass at the top of the picture.

Check the headspace of your rifle with a headspace gauge. If the headspace is properly set up, the bolt should close on a "go" gauge and should not close on a "no-go" gauge. If the bolt closes on a no-go gauge, there is excessive headspace and you should have a gunsmith check rifle and adjust the headspace.

If the rifle headspace is OK, then problem is the brass. You mentioned that the brass is new. You should check several samples from your lot of brass with a Mo gauge, an RCBS Precision Mic, or a Hornady headspace gauge (pictured in bigedp51's post above). The case head to shoulder measurement of your brass should be at little less (maybe .005 or so less than a "no-go" gauge). If the brass is shorter than that, then the brass is out of spec (for new brass) or has been sized back too much (previously fired brass). You can also measure your brass against brass in new, commercially-loaded ammo (Remington, Black Hills, military ammo, etc.). Your new brass should measure the same as known good, new commercial brass. As a previous poster mentioned, some LC brass sold as new might be "reject" brass.

Another possible cause for case separations (for previously fired brass) is that the brass has been previously fired in a chamber that is too long - that caused the brass to stretch, setting up the conditions for a case separation on the next firing.

You can get headspace gauges from PT&G, Midway or Brownell's. They are not cheap, but you really need to find the cause of the case separations.

 

[hogpatrol]

Here's my down 'n dirty headspace checking procedure, others may have something different.

Remove firing pin assembly from bolt. You can also remove the ejector but not absolutely necessary.

Insert desired EMPTY unprimed, trimmed to proper length case in chamber.

Take the bolt handle and try and move it forward then backward.

If you have "slop" or back and forth movement, you have a headspace issue, either improperly sized brass, out of spec brass or if brass is correct, chamber issues.

 

[bigedp51]

Here is a better method than moving/wiggling your bolt handle and far more accurate.

Take a new or full length resized case and measure its overall length and write it down. Next insert a fired spent primer in the primer pocket just seating the primer with your fingers.

Now chamber this test round in the chamber using the bolt face to seat the primer as you slowly close the bolt. Now measure the case again making sure your measuring from the case mouth to the base of the primer and write it down.

Now subtract the first case measurement from the second case measurement, your answer will be your head clearance or the air space between the rear of the case and the bolt face.

If your head clearance is excessive it will allow the brass to stretch and cause case head separations.

Having a Hornady cartridge case headspace gauge and measuring your fired case length and using minimum shoulder bump will prevent these case head separations.

 

[hogpatrol]

Here is a better method than moving/wiggling your bolt handle and far more accurate.

Take a new or full length resized case and measure its overall length and write it down. Next insert a fired spent primer in the primer pocket just seating the primer with your fingers.

Now chamber this test round in the chamber using the bolt face to seat the primer as you slowly close the bolt. Now measure the case again making sure your measuring from the case mouth to the base of the primer and write it down.

Now subtract the first case measurement from the second case measurement, your answer will be your head clearance or the air space between the rear of the case and the bolt face.

If your head clearance is excessive it will allow the brass to stretch and cause case head separations.

Having a Hornady cartridge case headspace gauge and measuring your fired case length and using minimum shoulder bump will prevent these case head separations.

I like that.