M*CARBO Brotherhood

Sub2k: Failures to Eject are endless. Asking for help

I have a Gen 1 Sub2k, full Red Lion build. I’ve had it since it was a couple weeks old and had never been fired- about 8 years total. It has spent the bulk of that time in the safe because I cannot get it to eject properly. I get constant stovepipes, and sometimes jams with the spent casing, and the new round in the ejection area. This happens every 4-6 rounds. It has been cleaned and lubricated to no avail. I finally installed the Mcarbo stainless feed ramp this week and took it to the range hoping that was all in the past. It immediately stovepiped on the first round and 8 more times over the next 50 rounds of 115g FMJ. I’ve tried Glock mags, Korean mags, multiple brands of ammo. Nothing has helped. I’m to the point that I want to sell it, and I have multiple buyers lined up, but I’m not comfortable selling it to them with this problem.

I tried to send it in to Keltec, but they told me since I wasn’t the original purchaser, they couldn’t help me. Is there anything I can do to solve this? Thank you for your collective knowledge. I really want to love this carbine, but I can’t trust it right now. I’m attaching some photos of the spent brass.

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Have you checked the extractor? Is the ejector straight in its notch? is the round end of the ejector facing the back of the gun and the angled end towards the front?

Judging by the primer indents, the bolt and chamber aren’t aligned - I’ve never seen a primer hit that far off. Is the barrel latching tightly to the receiver when you unfold the gun?

Since you’ve already tried different mags and ammo, and since it’s rare for the ejector to move enough to be an issue, I’m inclined to think the extractor is the problem. This is a blowback firearm so even if the extractor doesn’t grab the rim of the case it’ll still push itself out of the chamber. The extractor acts mostly as a pivot so when the case hits the ejector, the shell flips outwards to the right. Not enough flip = stovepipe, and it’s the front of the cases that are crushed, not the sides, so there ain’t much flippin’ goin’ on…

I’d try replacing the extractor and spring since they’re so inexpensive.

$4.50 - https://www.keltecweapons.com/product/s2k-180-extractor/
$1.20 - https://www.keltecweapons.com/product/s2k-182-extractor-spring/

Oh, and welcome to the Brotherhood, Scott. :smile:

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I had the same thing, I ended up tweaking (bending) the metal ejector tab untill it was a nats butt from touching the bolt. See red arrow. Check that clearance, this was before I fixed it.

It gets misaligned when you split the halfs and re assemble, the receiver tube gets a bit cocked. I decided to bend mine to prevent any future issues upon disassemble/reassemble.

Edit to add - my casings looked exactly likes yours do.

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Thank you so much for the welcome, and the advice. I’ll definitely order an extractor and spring.
I took photos of the ejector, extractor, and alignment from the barrel end. The ejector does appear to have the angled side forward, curved side back. It appears to be straight in the notch- flush against the bottom of the notch. Barrel latches tightly. no play that I can find.
It may be my imagination, but it almost seems like there is too much spring tension to overcome in the buffer. The bolt doesn’t seem to travel far enough to the rear to give the spent casing room, and time to eject before slamming forward again. I haven’t watched the charging handle to know…

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Thanks for the help! I think the extractor is pretty close to the bolt. I’ve attached a photo below showing position.

-Scott

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Hmm it seems the ejector is aligned decent but hard to tell at that angle. As for the alignment, it does seem to be canted a bit, but I don’t know if that will cause the off center primer strikes or ejection issues. Here are some pics of mine, a gen 2 though.


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How easily does the extractor move in its slot? Can you easily push it back an forth? You should feel some decent spring tension, its also possible you have no tension, and thus not getting secure grasp on the rim.

This might be a long shot, but i wonder if its possible the extractor isnt fully popping over the rim, thus pushing the rear of the case to the side during firing, then not pulling the case out to hit the ejector. Without that pull, the case just flops in the chamber, before getting rammed by the bolt.

Just thinkin out loud.

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My new Gen 2 did that the other day at the range. But only if I was pulling the trigger to fast. “Rapid” fire. It had 3 three rounds jammed up at the same time.

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Thanks for the photos. I can see the outline of the primer on the bolt face and it does appear to be off-center- low and left. That matches the spent casings pretty well.

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That sounds possible. I don’t know how practical it is that the extracter isn’t moving past the rim, but the behavior fits. It certainly doesn’t seem to be pulling spent brass back out of the chamber with any oomph. The extractor spring is strong, but it does move when lifted. More photos attached of extractor, bolt face, ejector from a better angle.

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I see that. Looking from the front of the gun with the bolt in it, the alignment itself looks okay. The primer like that indicates the bolt and barrel aren’t lining up, which is why I asked if the barrel was locking tightly when you unfold it. If the round is sitting that low, it might not be sitting flat on the end of the bolt and the extractor might only get a weak hold on the case’s rim, if at all.

Here’s what mine looks like. Note the centered primer mark.

image

Look at the rim of the case where the arrow’s pointing:

image

Have you shown this to a good gunsmith? I don’t know that we can do a lot for you

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Im not surprised that you cant getwarantee coverage, but have you asked either KelTec or Mcarbo to diagnose and repair it for a fee?

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Haven’t taken it to a gunsmith. I figured either Kel-tec or this group with be the most familiar to be able to diagnose. S2K is kind of a unique animal to have somebody diagnose if they’ve never worked on one. Kel-tec declined to look at it since I’m technically the second owner. I’m not sure that they’d even look at it if I paid them, since I’ve swapped the feed ramp with an Mcarbo unit.

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Naw, they’re used to MCarbo fixing their shortcomings. I’d at least ask a local gunsmith what he/she thinks. We’re mostly weekend gunsmiths here, using our experiences to suggest what to do next. My Sub2k is a good shooter and very reliable. I paid a lot more than it’s worth with all the upgrades but I don’t want to sell it. I know yours has been a PITA but you can at least try the easy stuff first.

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Hmm scratching my head here. But if you loosen the pivot bolts can you shift the barrel assembly up and down? Or is there any up and down movement in the barrel before its latched with the pivot bolts tight? Since its been modded quite a bit, did the pivot holes in the frame get oblonged or egg shaped. I’d imagine if it is that much off it wouldn’t latch properly. Could the foreend be interfeering in any way with alignment?

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Good questions- there’s no slop in lockup. Unfold, perfect lockup with no play in any direction. Not sure if there’s any way forend could cause issues. It’s pretty much downstream from chambering, so I’m not sure how it would. I could be wrong. I’m attaching a photo of the barrel & fold point. I do see some wear marks on the face. Not sure if thats typical factory stuff or not.

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The wear mark on the left side of the outside ring is “usual” but the ones on the feed cone aren’t real pretty.

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Find a 40 S&W case and put that on your bolt face in case your rifle got shipped with a 40 cal bolt and a 9mm barrel.

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Thanks for the Advice On the 40 cal bolt. Just grabbed a spent 40 cal casing and I cannot get it to seat in the bolt face. It seems a few thousandths too big.

I put a spent 9mm casing in the chamber, closed the bolt. I can hear and feel the extractor locking into the rim. I manually processed the bolt a number of times to watch the ejection. I know this will not approximate behavior when a round is fired, but the best I could do. I recorded it high speed:

Video of manual ejection- slomo

Video of play in bolt. Is this normal?

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If you do a frame-by-frame on the ejection video, it looks like the shell is coming off the extractor early. Normally, the front of the shell rotates to the right when it hits the ejector with the extractor acting as the pivot point, and the shell is kicked out of the receiver. This vid shows the shell coming off the extractor as soon as it hits the ejector, and rotating almost 180 degrees so the open end is facing the bolt, and then it rotates another 180 degrees out of the receiver.

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