Groves in 223 cases

[WhiteJEEPSmatter]

I have a fairly new barrel, has had a few rounds through it. Not many, never had an issue with it.

I keep my mags loaded like every good Samaritan should. Back up a little, it's a novekse barrel 1:7 twist 16", I've had it for many years on a build I never shoot but a couple times to test fire.

Fast forward, I had a Troy mag loaded so I thought I'd empty it at the range. At 100 yards the grouping sucked but it was only bore sighted so I didn't care until I picked up the brass because it's scored, groved, never seen it before.

The brass has perfect groves going around each pieces, some of the groves are on the inside as well. I'm not sure if it's the bcg, barrel or the ammo, I just put an m4e1 upper on it from aero and pulled the Vltor upper off, Daniel defense bcg, which runs flawless in other uppers, the ammo...well it's from a company out there in Vila Rica that use to frequent gun shows. Never has an issue with their ammo before.

So before I order a new barrel and new bcg has anyone ever seen this before?

 

[WhiteJEEPSmatter]

Oh and I tried many different mags, pmag gen 2 and 3, mtm, Troy, no metal mags were tried in the destruction of this brass.

 

[palmettomoon]

I'm a little confused by your post. Did you change the barrel and upper and the issue still presents or is it only with a specific barrel? You mention lots of variables in your setup but only the chamber of a barrel will score cases like that.

If it's a specific barrel, the chamber is rough due to chatter or improper reaming. It may be possible to rectify with polishing.

 

[WhiteJEEPSmatter]

I just changed the stripped upper to an aero upper, same barrel. I was thinking the barrel as well.

 

[palmettomoon]

I just changed the stripped upper to an aero upper, same barrel. I was thinking the barrel as well.

If there are deep grooves on the interior of the case wall, the sort that can be "scratched" with a sharp tool (I make mine from coat hanger wire annealed and bent at 90 degrees and sharpened to a fine point), that is indicative of incipient case head separation (assuming it's catching near the base or head of the cartridge) and that brass should be crimped with pliers and discarded. If it's catching higher up on the case wall and there is no discernable "bump out" on the exterior of the case, I'd discard those too.

If it's simply a light line and discolored due to be abraded, I'd reuse the brass. The manufacturer that you inferred made the ammunition doesn't screen every piece of brass they take in on trade or buys, so anything is possible but I'd not point the finger at them until I demonstrated the exact same thing happening in another barrel that is known to NOT do that with factory fresh ammo. But I suspect you know all this.

 

[jeep78]

You have a barrel that needs work or replacing.

 

[WhiteJEEPSmatter]

If there are deep grooves on the interior of the case wall, the sort that can be "scratched" with a sharp tool (I make mine from coat hanger wire annealed and bent at 90 degrees and sharpened to a fine point), that is indicative of incipient case head separation (assuming it's catching near the base or head of the cartridge) and that brass should be crimped with pliers and discarded. If it's catching higher up on the case wall and there is no discernable "bump out" on the exterior of the case, I'd discard those too.

If it's simply a light line and discolored due to be abraded, I'd reuse the brass. The manufacturer that you inferred made the ammunition doesn't screen every piece of brass they take in on trade or buys, so anything is possible but I'd not point the finger at them until I demonstrated the exact same thing happening in another barrel that is known to NOT do that with factory fresh ammo. But I suspect you know all this.

Correct, I don't think it has anything to do with the ammo, the issue is in the chamber. The feed ramps are extremely sharp, when I load a live round and eject it slowly there's no grooves in the brass but it cuts the projectiles up. I might take the barrel to a gun smith ans see if they can polish it if not I'll cut the chamber off and trash it.

 

[palmettomoon]

Correct, I don't think it has anything to do with the ammo, the issue is in the chamber. The feed ramps are extremely sharp, when I load a live round and eject it slowly there's no grooves in the brass but it cuts the projectiles up. I might take the barrel to a gun smith ans see if they can polish it if not I'll cut the chamber off and trash it.

I've had to knock sharp edges off feed ramps on M1A barrels but not an AR. Should be an easy fix if you dismount the barrel.

 

[Freshly Minted Georgian!]

Chamber problems could account for the rings on the outside of the case but not the inside. I'd go with palmettomoon first theory, that brass was at some point fired from a rifle with headspace issues.

Have you fired rounds from multiple sources out of the barrel in question? If so, did they all exhibit the rings?

 

[WhiteJEEPSmatter]

Yes, I shot some of my loads through it and it did the same thing. Destroyed the brass. I'll take it apart tonight and see if I can get a bore scope in there, in the mean time I'll order another barrel. I've been happy with ballistic advantage barrels so far.