FN Herstal Firearms banner

1 - 18 of 18 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter · #1 · (Edited)
Cleaned and greased the ps90 and I took it out to the range for the first time today and I'm lucky to get more than 1 shot off in a row working. Most cartridges that wouldn't fire have a mark on the side and there is no mark on the back. It's FN SS198LF ammo , so I would think the FNH ps90 would work fine with it. It seems like maybe taking the hammer pack out and back in would allow the gun to fire again for 1-2 shots. Also I'm not sure if it's related but one of the times i took the gun apart to try to find an issue, the bolt didn't want to come out and it probably took like 10 minutes to come out, despite it usually just sliding out. Seeming to get caught on something half way from the back. To get it out I had to put the barrel back in and use the charging handle and then take the barrel out and then the bolt would come right out. I've also tried firing with 2 different mags (one the factory mag) and had the same issue with both.
143153
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #3 · (Edited)
Damage like that would indicate an obstruction in the chamber which would also keep the firearm out of battery thus preventing the firing.

Check the chamber for a small obstruction like a case neck.
So i'm not seeing any obstruction in the gun, but If I try to chamber a new round with the magazine on, the first round isn't ejected. Then when I remove mag, using the charging handle ejects the round. It looks like the next bullet is getting in the way; which is weird because one of the mags it isn't working on is the one that came with the gun; I would expect at least that one to work if the mags were causing the issue. placing only 1 round in the FN mag that comes with the gun, and it still won't eject the bullet with the mag still in the gun. This is what happens after i pull the charging handle with a round already chambered. I am not holding it back to take this pic; it seems stuck back
143220
 

·
Registered
Joined
·
39 Posts
Most cartridges that wouldn't fire have a mark on the side and there is no mark on the back.
Do the failed cartridges have that mark on them to begin with or is the gun producing it?

How about some pics of the bolt face?
 

·
Registered
Joined
·
39 Posts
Also I'm not sure if it's related but one of the times i took the gun apart to try to find an issue, the bolt didn't want to come out and it probably took like 10 minutes to come out, despite it usually just sliding out. Seeming to get caught on something half way from the back. To get it out I had to put the barrel back in and use the charging handle and then take the barrel out and then the bolt would come right out.
This sounds like user error. If you dropped the hammer (pulled the trigger) prior to separating the receiver it would cause this behavior. In this case the breech block stop at the rear of the moving parts group would catch on the hammer itself after a short forward travel.
 

·
Administrator
Joined
·
12,015 Posts
Looks like the cartridge is not being ejected properly. If there is a round in the chamber trying to feed it another round won't work.

Do this outside. You are using a loaded cartridge.

Break down the firearm and remove the hammer pack from the firearm.

Assemble the firearm without the hammer pack installed.

Leave the magazine off.
Pull back the charging handle.
Place a single round in the chamber by hand.
Let the charging handle go letting the moving parts group move forward and placing the firearm into battery.
Pull the charging handle back.
The round should eject down the ejection port.
If the round doesn't eject, chances are the extractor on the bolt face is broken.
If the round does not eject, we need to see a picture of the bolt face.
If the round does eject properly your PS90 should have no cartridge in it.
Place 3 rounds into your magazine.
Place your magazine onto the gun making sure it is seated properly.
Charge the gun by pulling back the charging handle and letting it go.
A cartridge should strip off the magazine and feed into the chamber.
Repeat and a round should eject from the firearm prior to a new round being stripped from the magazine and clambering.
Repeat.
Repeat.
You should have completely cycled 3 rounds through your firearm.

If all three rounds feed and eject properly, the cycling of the firearm is correct.

Report back with your findings.

As an aside, you often can not visualize a broken case neck in the chamber without some bright illumination, however the picture above of a round in the chamber appears proper.
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #10 ·
finished the function check as instructed. The round ejects fine without a magazine. The first time i tried ejecting with the magazine, i got 1 round to eject and then further ones wouldn't. I took the mag off, emptied the chamber, and noticed the first round in the mag looked damaged. I got 3 more bullets, visually inspecting them first, and made sure they all visually looked in good condition and tried again. I was able to get the first round to eject and the first round in the mag looks extremely damaged; pushed farther into the casing
143263
.
 

·
Administrator
Joined
·
12,015 Posts
I still think there is a broken case neck in the chamber. Everything you are reporting leads to this conclusion. There have been several reports of these same symptoms on this forum.

The pushed in projectile has happened to many but discounting this (usually SS197 or AE ammo), the damage to the previous rounds, the inability to do a simple function check, the brass marring on the bolt, the failures to extract and eject rounds, these are all symptoms of an object in the chamber which typically is a broken case neck.

As mentioned earlier this would be very hard to visualize but I can not explain these symptoms any other way.
 

·
Registered
Joined
·
39 Posts
If I’m reading your description right, it sounds like the cartridges are being damaged while in the magazine. To summarize what I think I read: the round in the chamber fails to eject and the next round in the mag that would have been loaded if not for the FTE is severely damaged. Do I have that right? Where are you located? Maybe there’s a member near you that can take a look at it.
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #13 ·
If I’m reading your description right, it sounds like the cartridges are being damaged while in the magazine. To summarize what I think I read: the round in the chamber fails to eject and the next round in the mag that would have been loaded if not for the FTE is severely damaged. Do I have that right? Where are you located? Maybe there’s a member near you that can take a look at it.
yes, that's right. I live in northern Michigan
 

·
Administrator
Joined
·
12,015 Posts
The issue is the cartridge in the chamber fails to eject because it is stuck in there. The tension on the bolt face that holds the cartridge for extraction is insufficient to overcome the cartridge being stuck in the chamber. So the cartridge remains stuck in the chamber, meanwhile the moving parts group tries to strip and feed another cartridve from the magazine but the new cartridge has no place to go resulting in damage due to a failed double feed. Hence the pushed in projectile.

Solve the issue of why the cartridge fails to eject from the chamber and the problem is solved.

There does not appear to be anything broken on the bolt or bolt face, ergo something is holding the chambered cartridge in place.....a broken case neck or other foreign object.

I have seen this reported numerous times including members who have sworn that there was nothing in the chamber only to come back and say a broken case neck was stuck in the chamber.

My best analysis and guess without inspecting the firearm personally.
 

·
Registered
Joined
·
867 Posts
Forgive me if I'm stating the obvious but Do Not Fire any cartridges like the bottom one in your picture. That's called Kaboom town. The internal case volume has decreased significantly from design and pressure inside the case during firing will spike much higher than intended.

If I were you I would be sad to lose the time with the gun but send it to FN for service vs. risking your rifle and your health.
 

·
Premium Member
Joined
·
9,707 Posts
I just want to parrot the likelihood that you have something (probably a a case neck) in the chamber. It's easy to overlook. Shine a light in the chamber and get in there with a brass or plastic pick. Sometimes you can dislodge the obstruction with a brush.
 
  • Like
Reactions: M1P90 and dank
1 - 18 of 18 Posts
Top