Case head swipe?

[Lonehill]

I've got an AR I built in .223 Wylde. It's got an 18" Liberty barrel made by Satern running midlength gas system. Brass is ejecting at 1-2 o'clock even though I'm using a full mass carrier and an H2 buffer. Doesn't group well at all, right about 2 moa. I've only shot factory Hornady Varmint 55gn. Have had good luck with this load in all other AR's, although I've known factory Hornady to be pretty hot. Ejecting brass rather violently. Brass is marked up not only from the deflector but also at the case head. Looks like an arc a quarter way around case head. Matches pretty well with the bottom of the extractor recess. Upon further inspection, the bottom of this recess is a thousandth or two ABOVE the bolt face. Shouldn't they be flush or at least below the bolt face? Is this out of spec and is the root cause of all the rest of my problems. I want to resolve this cheap if I can, otherwise will get adjustable gas block to tame the gas and go from there.

[Lonehill]

Really? No replies at all? Any help appreciated!

[ThatRandomGuy]

I'm pretty much a newb but I have a similar system (Everything the same except 16" and standard buffer) so I'll try. What exactly do you mean by "bottom of the extractor recess". Looking at mine (Young NM carrier), I the extractor essentially has a lip, with a small recess underneath. There's definitely space between the bottom of the lip and the bolt face if that's what you mean, but the top of the extractor is below the rim of the bolt, if just barely. Now I believe with a 18 MLG you should have similar dwell time to a 16 Carbine, aka the gas can be a little much and have more of a recoil pulse. While the heavy buffer might slow said pulse, I'm not sure it would do anything towards helping with an overgassed bolt system.

Again, I'm still learning about AR's, just trying share what little I do know. My 16" MLG is a 223 Wylde, 5R AR Stoner barrel (so in all probability a Satern), YNM carrier. No gas problems, and it grouped VMAX 55gr in 1 moa right from the start with only a bipod on a bench and me never having shot an AR before, so I don't know why yours would behave so differently. Sorry if I'm no help.

[Lonehill]

Here's a pic. The semi circle shape at the bottom of the extractor groove is protruding above the bolt face. Shouldn't both pieces be flush? This is the exact same mark that's stamped on the case head of all my brass.

[Lonehill]

Here's my brass, notice how chewed up they are. Left side is factory Hornady 55gr V-max, right side is some old factory Winchester 55gr PSP I had laying around used to see if the ammo was the problem. Primer strike is very heavy, actually pierced one of the Winchesters. Case on upper right has an additional horizontal indent that is quite perplexing. Spike's Tactical BCG. Took apart upon initial assembly (removed extractor to get true measurement) and checked headspace with .223 Wylde Go/No-go. GTG so I reassembled and ran it. Couldn't find all my brass. Ejecting at least 15 ft. @ 1:30. Pretty wicked.

[ThatRandomGuy]

Ok, I see what you're talking about. Yes, in my bolt that piece is slightly below the face, just noticeably. Tried to take some closeups at what mine looks like. But dang, that brass... Now, I'm guessing you don't have another bolt/extractor to try or you already would have, but do you have any friends/range mates you might let you try theirs for a few rounds just to test if that's the problem?

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[Lonehill]

Got a Remington R-15. Sub-MOA from day one. Functions flawlessly. Extractor is couple thousandths below the bolt face. Guess I could swap just the extractor with no need to re-headspace. Sure hate to change ANYTHING on that rifle though! I've shot lots of crows and prairie dogs at 350yds + with it. Further on coyotes. Thanks for the suggestion, I'll give it a go. Does anybody know if this is for sure out of spec? Spikes is usually first rate. I've had 4 AR's and none of them were above flush on the extractor and none of them chewed up brass.

[Lonehill]

Swapped extractors between the two. The suspect one outta the ST is now on the R-15 and it is perfectly flush. Should run fine. The one from the R-15 now on problem rifle and is actually a thous. lower than the bolt face. Gonna run em both and go from there. I'm probably still way overgassed but we'll see. Also, the R-15 firing pin looked more blunt on the business end and noticeably shorter. Mic'd it and sure enough, R-15 measured 3.276 and ST measured 3.279. Three thousandths extra would definitely be more prone to punch primers. Might address that too.