Could you give us any information as to what brand and configuration of rifle?  It looks like there is a slight mark from the ejector.  I would check the headspace to make sure it is a 5.56 chamber.

CY6
Greg Sullivan "Sully"
SLR15 Rifles
TheDefensiveEdge.com
(763) 712-0123

Either bur on the bolt face at the extractor channel, or the extractor bottom of rim relief channel has a bur instead.

Post photo bolt face without the extractor, then a good photo of the bottom of the extractor rim relief channel, and I will circle the burs that need to be removed to solve the problem quickly, or you can let the burs self remove/polish off through live fire instead.

Ammo does not appear to be sighs of over pressure looking the primer.

Instead, looks like the bottom of the rim relief channel on the extractor has a bur, and is proud of the bolt face recess channel, and what is causing the problem.

Again, photos would help (one of the extractor in the bolt as well) since I would almost bank that the extractor is out of spec.

Take a look at the photo below and on the right hand bolt, notice how the extractor bottom of rim relief channel if slightly before the face of the bolt, and the bolt face channel it self does not have any burs.  This is the ideal set up.
As for the bolt on the left, extractor is out of spec, and will see that it seats too far in on the bolt face (circluar edge of the bolt face recess wall line), causing for a hell of a time for the round's rim to be able to climb past it/ push it out and being able to ride down the angled part of the extractor on loading.

"A" problem????   I can count about 4 of them from what I can see  just in this  above photo.

Starting on the edge from the extractor side channel, to the bolt recess surface, that entire edge of the bolt face is one long high ridge/bur.


Next run a pick tool from the bolt recess face surface, to the extractor bottom relief channel surface that is in line with it.  Instead of the pick tool dropping slightly down as it leaves the bolt face surface and start to track across the extractor rim relief surface, the the tip of the pick tool would needed to step up instead.   Then on the same extractor bottom rim recess surface, both edges have nasty burs as well.

Get the supply on the phone to have the entire Bolt replaced; extractor and all!!!

Pull the extractor, and run the tip of a sharp knife from the firing pin channel outward past the edge of where the extractor channel starts on the side of the bolt.
When the knife tip gets to the edge of the corner where the extractor channel starts, the tip is going to hit the first long bur across that entire edge of the bolt face.

Now put the extractor back in, and do the same with the knife edge, and take is all the way inside to the side wall of the extractor channel (inside the case rim relief channel of the extractor).

Now with the tip of the knife hits the extractor start edge, instead of the tip of the knife dropping down a touch to drop onto the extractor rim releif channel surface, the tip is going to stop since it is hitting edge of the extractor flat section that protruding above the face of the bolt instead.

Now when you have the tip of the knife inside the extractor rim section, move the edge left and right, and you will be hitting burs on both sides of the extractor channel as well.


So  with the extractor off the bolt, the first ridge/bur that needs to be clean up this one on the face of the bolt to make sure that the entire bolt face is smooth and level.


If you look at this case, it the dent cause on it.





On the extractor, it needs to be milled to lower the bottom ledge of the rim releif channel down  so it does not protrude above the bolt face surface , then clean up the side burs after is have been lowered, so as the bolt rotates around on the rim and slightly cants the extractor in the bolt channel, it does not shave the rim brass .


This is what causing the brass shaving in this photo.


Now the reason to send it back, instead of trying to clean this mess without mill yourself, both the bolt and the extractor are heat treated, and the standard HSS type files you try to use, will not even scratch the metal of the two (at most, will just end up filing the parkerizing off).

Noveske is very good about holding their dimension in regards to head spacing, so the replacement bolt should held head spacing  fine as well.

But on that note, if you do suspect a head spacing problem (not seeing over pressure problems via the spent primers) , then best to send the entire upper back to be checked.   The reason for this is the barrel itself is most of the head spacing math (barrel extension front of lugs to the chamber that could be off).

Not bad, and about the same 10 round size groups that I get with Wolf 62 grain steel case ammo out of one of my NM rigs (iron sights) when benched at 100 yards (1/8 NM barrel).

Give the barrel some time to unify in, and with hand loads to make the rig really sing, should be able to group much tighter.

The barrel needs to do a few things before it will group it's best.

The throat of the chamber (and maybe even the muzzle) may has some small burs that need to knock off via live fire so the bullets are embedding cleaning into the rifling at ignition jump (and exit cleaning in the case of the muzzle).

The steel of the barrel needs to stress relive (again, through live fire).

The lands and grooves of the rifling need to unify by the bullets moving down the bore (through live fire again, so try to keep the bore clean to allow this to happen quickly).

Hence,  On a barrel that was not hand lapped to do the above, give the barrel around 300 rounds to unify in, and it should shooting it's best by then.

Use something like Sweets copper solvent to clean the bore (removes the copper quickly without the need of a lot of scrubbing), then switch over to CLP to clean the rest of the rifle, including the chamber with chamber brush. The Sweets leaves behind no protective layer coating, and the CLP from the chamber cleaning pushed down the bore will be enough for short term storage to protect the barrel bore from rusting (even SS can rust).  Then, before you go to the range, just use a cotton mop with alcohol to remove any of the CLP in the chamber (read the Teflon in CLP takes around 14 shots to fully clean it out of the bore).


Hence, part of unifying the land and grooves, is to allow the copper bullets to polish the surfaces as well, and  if the surfaces of the barrel are copper gilded, then the bullet is not polishing these surface, but instead just passing over gilded surfaces instead.

So no, you don't need to keep the barrel spotless for a extended break in period, but you do want to get all the copper out of the barrel at cleanings instead (without needed to do a lot of scrubbing, since more rifle barrels are destroyed by over scrubbing, then actually being shot out instead.