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ATTN: Cartridge Stopper QC Issue for Pump Actions (FTF)

Water Monkey

The man, the myth, the monkey
Moderator
Supporter
Based on several complaints, including myself, it seems there may be a QC issue relating to Mossberg's Cartridge Stopper which is causing a specific operation failure - Failure To Feed (FTF) from the magazine tube upon racking the slide.

ISSUE IS A FOLLOWS:

Seems the Cartridge Stopper is bent too far during production.

CAUSATION OF ISSUE:

Because the Cartridge Stopper is bent too far the action slide rod is going behind the Cartridge Stopper instead of infront of it. It MUST go infront of it in order to cause the shell to eject from the magazine tube.

CORRECTION OF ISSUE:

Take the Cartridge Stopper out of the receiver and bend it in the opposite direction in an effort to make it straighter. This will take some effort so dont be afraid to put some gradual and consistent pressure.

Place the Cartridge Stopper back into the receiver and try and cycle dummy rounds until you get consistent ejection results.

Repeat this step as many times as necessary.

IF LEFT UNCORRECTED:

You will wear down the Cartridge Stopper and the Action Slide Rod which will cause you to replace both items at a cost of approximately $60.

See my post for examples of excessive wear at the 400 round mark:

viewtopic.php?f=22&t=4174
 

aksavanaman

Work In Progress...
Supporter
"Philanthropist"
aksavanaman said:


This shows the Cartridge Stop on the right side of the receiver in action.



This picture shows the interrupter (on the left) in action. The interrupter keeps the shells in the mag tube as the lifter chambers a shell.



This picture shows the right action bar as it's actuating the cartridge stop. Notice how the cartridge stop is starting to ride behind the action bar... a common problem occurs when this stop rides in front of the bar causing a bind...

And then there's the bent cartridge stop lever that doesn't quite move far enough to allow the shells to enter the chamber....
 

John A.

Unconstitutional laws are not laws.
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I am going to have to replace both the cartridge stop and the Cartridge Interceptor Assembly in my 500A.

It has started to cause an intermittent failure to feed and I cannot have that.
 

nitesite

Average Guy
Moderator
"Philanthropist"
How many owners of Mossberg pumps who have been affected by this poor QC will never be known it seems. Damn shame it wasn't caught real early by OFM and corrected properly, including free parts to consumers.
 

John A.

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To be honest nitesite, this isn't the first issue my one and last 500 has.

The mechanical safety has not worked in probably 8 years either and they seemed generally uninterested when I called them to report the problem and to ask that they repair it.

But I will guarantee that they better pray it never goes off and hurts anyone because of it because I do have documentation and call recordings.
 

Tanker

.270 WIN
I am still unclear on what to modify. Can yo update with arrows pointing to what needs to be tweaked? THanks, Ron
 

GunnyGene

Racist old man
BANNED
I've only had my 1989 Mariner for a few months, so maybe the previous owner fixed all the problems that are talked about here. It hasn't given me a lick of trouble since I've had it, and fired maybe 50 rnds of various loads thru it from birdshot to slugs.
 

LAZY EYED SNIPER

Overwatch
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"Philanthropist"
From what I've seen in my time on the site this is a recent issue.

The likely cause is a big batch of out of spec parts that were installed and made it through QC without anyone noticing. Either that, or they did notice but let 'em ship anyway. Either way this is a pretty widespread issue on models made within the last two years or so...
 

GunnyGene

Racist old man
BANNED
LAZY EYED SNIPER said:
From what I've seen in my time on the site this is a recent issue.

The likely cause is a big batch of out of spec parts that were installed and made it through QC without anyone noticing. Either that, or they did notice but let 'em ship anyway. Either way this is a pretty widespread issue on models made within the last two years or so...

Well that makes me feel better. And really smart ;) :lol: . Before I found this used Mariner, I'd been looking at new 500's and 590's and nearly bought one.
 

old mossy

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Tanker said:
I am still unclear on what to modify. Can yo update with arrows pointing to what needs to be tweaked? THanks, Ron

the problem is with SOME of the cartridge stoppers.
if you are having a problem with your gun,email mossberg and they will send you another.
you can fix it yourself with some patients and a few tools to straighten or bend it. if your not having a problem,leave it alone.
below is a pic that shows the cartridge stopper.
 

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John A.

Unconstitutional laws are not laws.
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old mossy said:
if you are having a problem with your gun,email mossberg and they will send you another.

OK, I'll try that.

I sent them an email on their website contact page.

Let's see if I even get a timely reply.


Good evening.

I have a Mossberg 500A and sometimes it fails to feed a shell from the mag tube. It appears that the cartridge stop and cartridge interceptor assembly is bent incorrectly.

I was writing to ask if you can provide me a new cartridge stop and Cartridge Interceptor Assembly.

Thank you,
contact info


Thank you for contacting Mossberg. A representative will be in contact with you shortly.

Go back to the form
 

old mossy

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Tanker said:
Thanks. When I get mine (hopefully this week, Bud's is slow), I will have to give it a work out. Ron

don't forget the pics. :D
 

Tanker

.270 WIN
I think I may understand, so correct me if I don't have it. On the pic with the red circle, the part(action rod) where the red arow is has to ride behind the part (cartridge stop) where the green arrow is. Right? Ron
 

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Tanker

.270 WIN
Great
When I get mine and the red arrow part(rail) rides behind the the cartridge stop, I will be relieved!
They said it is in shipping now, so hopefully I will have in hand by Wednesday or Thursday.
Then the pics. Ron
 

old mossy

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a big thing i've noticed is when a gun starts acting up(not racking as smooth as it was) a lot of people force the action and wind up bending and doing more damage to the gun.
if you know the feel of your gun and all of a sudden it changes,,,,,STOP,,,don't go forcing things.
take a real good look at what's going on with it. JMO.
 

Tanker

.270 WIN
When I say behind, that means the cartridge stop is pushed to the receiver side and the rail comes back over the cartridge stop and completely covers it when slide is full retracted.
I think I was confusing what behind meant. When operating correctly the slide rail completely covers the cartridge stop and you do not see the cartridge stop. When they say behind, they mean the rail rides between the reciever and cartridge stop.
The slide rail has a bevel and the cartridge stop is bevels and the only way it woudl work correctly is by pushing the cartridge stop to the reciever side.
Ron

Tanker said:
I think I may understand, so correct me if I don't have it. On the pic with the red circle, the part(action rod) where the red arow is has to ride behind the part (cartridge stop) where the green arrow is. Right? Ron
 

John A.

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Old Mossy, I received a reply to my email today.

Thank you for your e-mail. Sir I will send you a replacement but please forward me your serial number so I can send it out. thank you.

Quite a change from my last experience with their customer service.
 
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