M*CARBO Brotherhood

Sub2k: Failures to Eject are endless. Asking for help

I have a new extractor and spring on the way From KT. No idea if it will make a difference. Anyone replaced an extractor? Any tips?

-Scott

phuzzy42 Regular
September 17

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.

2 Likes

It’s no biggie. Drive the pin out with a punch, but keep your finger over the extractor when you do so the spring doesn’t fly the friendly skies.

1 Like

The bolt is coming back with the shell still on the extractor…

The shell hits the ejector here…

The bolt is still traveling back, the shell is OFF the extractor at this point…

The shell does a 180 inside the receiver…

It continues spinning…

And out the ejection port…

I’m inclined to believe the extractor is the culprit, or at least a major contributor.

Mine gun’s bolt has a little play but not quite as much as yours. It’s from the connection between the bolt and bolt head. I don’t think it’s significant.

Any other brother want to chime in on this?

2 Likes

Wow. Impressed with everyone’s breakdown of this. I need to take it back to the range and catch a failure on high-speed. So much appreciated.

-Scott

phuzzy42 Regular
September 17

The bolt is coming back with the shell still on the extractor…

The shell hits the ejector here…

The bolt is still traveling back, the shell is OFF the extractor at this point…

The shell does a 180 inside the receiver…

It continues spinning…

And out the ejection port…

I’m inclined to believe the extractor is the culprit, or at least a major contributor.

perma:

Video of play in bolt. Is this normal?

Mine gun’s bolt has a little play but not quite as much as yours. It’s from the connection between the bolt and bolt head. I don’t think it’s significant.

Any other brother want to chime in on this?

1 Like

Your videos are very good - they help show what’s really happening. I use VLC to play almost every media file there is - video, audio, DVD, etc. and it’s free. It can do the frame-by-frame and take snapshots like above. I’ve been using it for years.

4 Likes

Extractor letting go too early can still be caused by a misaligned chamber/bolt interface, with the case sticking and being dragged off the extractor early. Maybe because of the play in the bolt? Mine doesnt move that much, but im still under 1000 rds through it.

2 Likes

It is a blowback action. Case isn’t sticking; it’s pushing. I’d surface the extractor to eliminate engagement issues with the case rim. Next I’d take a detailed look at the ejector. Is it oriented correctly? Why isn’t it ejecting on impact with the spent case?

1 Like

Just a shot in the dark here, is there any sign that the bolt is dragging. The only time I have ever had a fail to eject, I discovered that there was a burr at the front of the charging handle slot. I was slamming the bolt forward when the sub was folded cuz it sounded cool. If there is nothing to stop the bolt face ( like the chamber ) the charging handle impacts the slot and deforms it. Just a thought.

4 Likes

Right, sorry. poorly described on my part.
I was trying to point out potential friction of the case against one side of the chamber upon exit, due to misaligned bolt stroke. Seems like excess motion, or friction could break the extractor’s hold?

3 Likes

Thanks, everyone for your assistance over the last week. In the very first reply, to my request for help, Phuzzy42 suggested replacing the extractor and spring. I ordered them that day, and they arrived this morning. Installed them, and took it to the range. For the first time in eight years, it just worked!

Thank you, Thank you, Thank you.

I took photos of the new vs old ejector and spring. The new ejector is narrower, but has a much firmer grip on the rim with that longer spring. Hope this thread helps someone else down the road.

12 Likes

Glad to hear it, and glad it didn’t cost you an arm and a leg. I think you’ll be happy you didn’t sell this gun - it’s a fun shooter.

5 Likes

Was that “growth” on the extractor that way from the factory? That couldn’t have been helping you there… :hushed:

3 Likes

It was that way from the factory. I just assumed they were all that way. My new extractor had a different manufacturing defect. I filed and polished it prior to installation to avoid any new issues.

chilipepper
September 20

Was that “growth” on the extractor that way from the factory? That couldn’t have been helping you there… :hushed:

4 Likes