Scratches on .223 brass--why?

[mongoose33]

I went out last weekend shooting up some of my x-die-sized .223 reloads out of my M4. Tonite, when I was sorting brass and inspecting it, I discovered a pattern I don't like: two small marks on the necks of the brass, like so:

The scratches show that they were created, more or less, upon extraction.

So what's going on here? Do I have dirt in the chamber, or worse, a scored chamber that's causing this? I tried to look at the chamber w/ a small LED flashlight, but was unable to determine anything.

I also tried to feel around the chamber w/ a piece of copper wire, but that wasn't very successful.

Am I right in concluding I've got something in the chamber scratching this brass? What do I do other than try to scrub it out? Or am I missing something here?

 

[Remo-99]

To me it just looks like the necks have 'kissed' an edge(ejector port???) during ejection.
If it was from a rough chamber or something like that, then all the cases would have the marks which would also be sooted like the rest of the necks are.
That's just my interpertation of the pics, though.

 

[Runningman]

Looks to me like the necks are hitting the barrel locking lugs on extraction. Does it do this with factory ammo?

 

[NCsmitty]

Not to change the subject, but your fired rounds have more of a problem than a couple marks from ejection.
If I observed the smoking down the case such as you have in the picture, I would be concerned that my load is not developing proper pressure to seal the case to the chamber.
Not owning an M4, I don't know if that is a common thing or not.

I do know that in my T Contender, proper pressure developed in my 223 will show a light smoke down the first 1/8"to 3/16" of the neck.




NCsmitty

 

[kestak]

Greetings,

Checked my 223 brass 55 grains SP Hornady, 25.1 grains of Ramshot TAC. I do have that kind of smoking too. It is occuring in 3 RRAs, 1 SIG 556 and 1 FS2000.

I was concerned at first, but the chrono is good and it cloverleafs at 100 yards.

Must I be concerned????

Thank you

 

[Remo-99]

If it's a gasgun theres gonna be smoked case necks to some degree. It's just the nature of the beast.

 

[delta5]

Could there be a burr in the chamber?

 

[Walkalong]

Must I be concerned????

Nope.

Interesting marks. I dunno.

 

[stingrr]

I would say something on extraction myself.

If it was in the chamber, I don't think the marks would be shiney.

 

[mongoose33]

Looks to me like the necks are hitting the barrel locking lugs on extraction. Does it do this with factory ammo?

I don't know. I don't shoot factory ammo.

At least, it's been a long time since i have.

I am thinking that perhaps you're right--this may be from the brass kissing the locking lugs on ejection--as they appear evenly spaced and very close to exactly the same on each case.

I'm not happy w/ the gouges/scratches. I resized a couple in my X-die, and they smoothed out, but I'd think this would hasten the day when the neck splits and renders the brass useless for reloading.

 

[Plas62]

I have similar marks on my .223 brass, which I just started reloading for. I would be interested to know if any one has any thoughts on how to correct this issiue or if this normal.

 

[cougar1717]

Very normal. Any semi-auto rifle is harder on brass than a bolt action. AR brass usually wears out when it stretches near the case head, forming a bright ring where the brass is thinning. This should occur before the neck splits.

 

[W.E.G.]

A non-issue.

The brass is smacking the lugs on the barrel extension on the way out.

 

[Rokman]

I have the same marks on my brass from my AR ammo.