Mossberg 930 Autoloader Troubleshooting

Discussion in 'Mossberg 930 Autoloader' started by DHonovich, Sep 3, 2010.

  1. DHonovich

    DHonovich Founder Staff Member Administrator Sponsor "Philanthropist"

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    6,650
    Any issues, concerns or problems you may have with your mossberg 930 autoloader; this is a thread for troubleshooting.
  2. Mudinyeri

    Mudinyeri Sponsor Sponsor Forum Moderator

    Messages:
    792
    Wow! Nothing here. Everyone's 930 must be running flawlessly. Unfortunately, I had no such luck with this weekend's outing with mine. Guess the Newb is going to have to open things up. :lol:

    First, a little history ... I purchased my 930 SPX about six months ago and have run about 500-600 rounds through it with only a couple problems until this weekend. I've run all kinds of ammo through it from inexpensive 00 Buck, to slugs, to Winchester Super X and Winchester AA birdshot. Everything has been 2 3/4". The Winchester Super X caused the most problems but I had problems with every type of ammo this weekend.

    The problem is a failure to feed. The round being fed hangs up on the feed ramp at the top of the reciever. With the Winchester AA it was consistently the last round of the magazine. With the other ammo it seemed to be random.

    Any thoughts? I had cleaned the gun before this weekend's outing but ran about 200 rounds through it altogether. The gun was fairly "dry." I'm not a big fan of a lot of oil on my guns. I also recently added the Choate charging handle. Other than the Choate handle and a sling the gun is stock. I didn't have the stock charging handle with me to switch back and see if it made a difference.

    Thanks for your help.
  3. FOX3

    FOX3 .410

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    94
    Mudinyeri, first off welcome. Glad to have you. My 930 runs flawlessly after over a year of ownership, 2 3/4" 3", birdshot, buck shot, bean bags, no problems. A squid friend of mine happens to own a 930 as well, and experiences the same problem you speak of although only when using birdshot. know the problem is not the charging handle as his was stock. I'll keep at it and let you know what I find out.
  4. Mudinyeri

    Mudinyeri Sponsor Sponsor Forum Moderator

    Messages:
    792
    Appreciate it FOX. I gave it a serious cleaning Tuesday night.

    Interestingly, there was some brown colored stuff that came out of the magazine when I sprayed spray solvent into it. Rust? It sits in my dehumidified safe.

    There's also a very obvious wear mark inside the receiver. It's almost like a light gouge. I'll see if I can get a decent picture of it. I can't tell if it's from the bolt moving inside the receiver or from the back (brass) end of the shells passing through the receiver.
  5. m24shooter

    m24shooter Forum Moderator Forum Moderator

    Messages:
    455
    The brown stuff could be leftover preservative that was never cleaned out of the mag tube. Mossberg is known for having a lot of funk in their shotguns.
    As for not cycling, I'm not sure what you're describing as the feed ramp at the top of the receiver.
    In terms of lube, even though you may not like doing it my 930 has run better with more lube.
    Also keep in mind that the 930 SPX is meant to be a defensive gun, shooting defensive loads. Some people never have problems shooting the lighter loads, and some people do.
    I'd like to see the gouge too. The brass wouldn't be able to gouge the receiver, but if the bolt is doing it there's something else going on.
    Have you ever removed the bolt and cleaned out/off the plunger that extends into the action spring in the stock? Sometimed that thing can get pretty nasty and it will slow the bolt down enough to cause some problems.
  6. Mudinyeri

    Mudinyeri Sponsor Sponsor Forum Moderator

    Messages:
    792
    I cleaned the bolt after I first purchased the shotgun. I didn't clean the mag tube.

    I've taken some pictures of the "gouge." It really isn't a gouge. The area is smooth. It's almost like the receiver had a little bit of extra metal that has been rubbed off by the bolt. Note the area indicated by the arrows in the two pictures below.

    [​IMG]

    [​IMG]

    The area that I'm referring to as the "feed ramp" is immediately forward of the indented square seen at the top/forward area of the receiver in the two photos above. It is a "ramp" that allows the top/front of the shell to slide into the barrel as it is pushed forward by the bolt.
  7. O'DubhGhaill

    O'DubhGhaill .22LR

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    24
    Mudinyeri, I have never seen a wear pattern like that. Be that as it may, you should definitely clean out your mag tube. I have read of rounds hanging up at the end of the mag tube where the Choate extension begins due to a slight ID difference between the two. Also, I have read that Mossberg shipped some early 930s with a mag spring that was not long enough? I think I read the spring should be 28" long? m24shooter?

    The "minor factory assembly defect" I wrote of in the HD thread and that you asked me to elaborate on via PM involved the gas pressure ring and the split washer that fits inside that ring (this is the gas ring that is pressed behind the heavy recoil spring in the body of the gas port assembly attached to the barrel). The split washer "appeared" on the mag tube when I initially disassembled for cleaning. I thought it was the gas seal mentioned in the manual, the one that Mossberg states may or may not be on the 930 SPX one received. I put it back on the mag tube according to the manual and reassembled. At the range, the only thing that would cycle the gun was slug. Upon dissassembly, I couldn't find the split washer. I eventually noticed it pressed at an angle behind the gas pressure seal in the area in front of the gas ports - I did not have full pressure sealing! I disassembled that section, removed the part, bent it back to shape, reinstalled it inside the correct seal, reassembled and no problems since.
  8. Mudinyeri

    Mudinyeri Sponsor Sponsor Forum Moderator

    Messages:
    792
    I cleaned my mag tube after last weekend's outing but haven't had a chance to get back out for more testing yet. Might be able to sneak out tomorrow afternoon ....
  9. m24shooter

    m24shooter Forum Moderator Forum Moderator

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    455
    Joe:
    The springs should be about 28"or thereabouts. Choate/OFM have had some that were almost 40" and then there have been a few of the very short springs that are meant for the standard 930 in the SPX as well.
    Mud:
    That wear is NOT normal. Mine doesn't look like that, and I haven't heard of that.
    The area you're talking about is actually cut off in the pictures. For some reason that the admins are working on, the board clips the extreme right side of the pics posted here. That said, if the shell is hanging up there that is indicative of another problem. The feed ramp is actually the bottom edge of the rear of the chamber, and will be the area immediately at the 6 o'clock position of the barrel and between the barrel and the mag tube opening. If the shell is actually hitting the top of the reciever in the area you're talking about and hanging up there, that is not normal.
    When you have your bolt out, clean that plunger that attached via the link on the back of the bolt and pushes down into the action spring in the stock. It may be a good idea to remove the stock and spray some degreaser/cleaner in there, and then relube it. Make sure that the plunger has full and easy travel through the action spring.
    Make sure that the follower moves freely through the mag tube, and make sure that the bolt is moving freely in its raceway as well. Then try lubing it generously and seeing if all of that helps.
    If you still have problems, then it would be time to call Mike Shain at Aimpro or the Mossberg Service Center. It would probably be a good idea to check with either of them on the wear in your receiver as well. I would try to talk to Mike first if you can get him, and ask if you can send that pic to him so he can see what you're talking about.
  10. tgw

    tgw .22LR

    Messages:
    33
    Replacing Safety

    As on my 590A1, which has the metal safety, my 930 has the plastic safety held on by a screw with the head designed to not allow removal with a screw driver. How does one remove this screw in order to install one of the after market metal safeties?
  11. Rossignol

    Rossignol The Original Sheriff Staff Member Global Moderator Sponsor Forum Moderator

    Messages:
    9,363
    Re: Replacing Safety

    Good question!
  12. hunter72

    hunter72 .223

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    103
    Re: Replacing Safety

    Im not very familiar with the 930 yet, however if I understand you correctly its the same type of one way screw as the 500/590 safety.
    If that's the case almost all of them that I have converted to metal have been able to be removed by a reguliar slotted screwdriver.
    Use a a bit that would fit the screw if putting it on, tighten just a hair then push harder and back it out. I have changed over 60 of them this way.
    On the 2 or 3 I couldnt get to move I dremeled a small slot and used the smallest bit I had.
    Its all about pressure and going slow till it breaks loose.
  13. m24shooter

    m24shooter Forum Moderator Forum Moderator

    Messages:
    455
    Re: Replacing Safety

    Put the shotgun in a padded vise, with the bolt locked to the rear.
    You have two options. I've done both, and actually was able to get through a large number of departmental guns with the second method which is quicker and safer obviously. Sometimes you have to destroy the screw though.
    1. Dremel method-Mask off the receiver around the safety with heavy tape. Use a cut-off wheel and cut a cross slot in the screw head, being careful not to cut all the way through. Once you have a slot big enough for a small driver just back the screw out. Replace safety and use a new screw.
    2. Driver method-You may want to mask the receiver just to keep from scratching it since some force may be needed. The best tool is a gunsmith's driver, sized wide enough to fit the screw head. Gunsmith drivers are squared on the tool edge, and not beveled. That's why you frequently see scratched/worn screw heads on guns: people don't have or use gunsmith drivers and the beveled tool edge slops in the squared slot, allowing the driver to fit loosely and mar the screw head. Press down on the screw head with the driver and back it out. You may want to tap the handle of the driver with a nylon mallet to seat the driver bit and help it bite into the screw head. Back the screw out while pressing down.

    Tips for both-
    Make sure the bolt is locked to the rear. That way the mechanism doesn't drop into the receiver.
    You can use a small dab of grease to keep the ball bearing from falling/rolling out of the recess in the receiver.
    If your safety comes with a backing plate (the metal piece with 5 holes in it) USE IT. It helps to prevent wear on the underside of the safety, which can result in the safety flipping on after each firing. Be advised that some safeties don't come with them, but still need them. These usually don't include ANY other parts like the screw, detent, and spring and you basically just get the safety button. Brownell's sells the safeties as a kit, and also just the button itself in some cases, so be aware of what you will need.
    It may be a good idea to make sure that your safety comes with a new screw. Not all suppliers include the screw, and if you ever need to replace the safety it is a lot easier with a conventional screw or a hex version. I've had to help several people that cut through their safety screw only to find out when they open the safety packaging that they don't have a screw to secure it with now.
  14. tgw

    tgw .22LR

    Messages:
    33
    Re: Replacing Safety

    When I get the existing screw off using either method and I lift the existing safety off, what will I see? If the replacement includes a new slotted screw do I just replace the safety at that point or do I need this plate that is mentioned?
  15. hunter72

    hunter72 .223

    Messages:
    103
    Re: Replacing Safety

    Use the plate, what you will see is a small dentent ball-IT IS NOT FIXED INTO PLACE IT WILL FALL OUT-
    take off the plastic safety, the plate may stay in place, put the new safety on and tightend down the new screw-checking the safety for free movement.
  16. jaxman7

    jaxman7 .22LR

    Messages:
    16
    Re: Replacing Safety

    This info will come in handy for me tomorrow. I should be receiving my safety from ETA tomorrow finally. It has taken awhile to get this in because about the same time of my order ETA changed materials (from 6000 to 7000 series aluminum) and the components of their safety. I must say Mark of ETA has been great and given great comms in relation to the delay. Also he offered me one of their followers for free to make 'ammends' for the wait. Will keep y'all posted when I receive mine and how I replaced my stock safety.

    -Jax
  17. m24shooter

    m24shooter Forum Moderator Forum Moderator

    Messages:
    455
    Re: Replacing Safety

    You will see the metal backing plate. It should be bright metal but I have seen some that were blackened. It will have one hole in the center, and a pair of holes above and below this. This will be under the safety button and if you are carefull and don't have too much oil/gunk seeping into the space between it and the bottom of the safety it should drop free of the safety when you remove it. It may stick to the bottom of the safety and you'll have to pull it off the bottom.
    As mentioned, that BB will fall out if you aren't careful. That's where a little dab of grease on the BB will help to hold it in place.
    This is what you will see with the safety AND the backing plate removed.

    [​IMG]

    You can see the safety mechanism with the threaded hole that the safety screw screws into, the BB, and the red safety off indicator.

    In most cases you will still need the plate. The plate prevents the detents on the underside of the safety from wearing out and allowing the safety to move under recoil. If you use the safety a lot you can erode the edges of the detents, which will allow the safety to re-engage when you're shooting. The backing plate prevents and/or lessens this.
    Some safeties could bypass this by using very hard materials that would negate the use of the backing plate. While it wouldn't hurt to include the backing plate regardless of the safety used, if you don't include you may have a problem down the line, so it would be kind of an insurance policy in that case.
  18. DHonovich

    DHonovich Founder Staff Member Administrator Sponsor "Philanthropist"

    Messages:
    6,650
    Today during a sporting clays tournament I experienced my first FTE with my Mossberg 930 autoloader. To be fair though I had over 600 shots through it before this event without thoroughly cleaning it. Additionally another one of the competitors was having trouble with their shotgun and ended up borrowing mine so we shot it back to back at each station. Overall during the event it performed flawlessly. It was quite comical because the two other autoloaders (both higher end benelli's) had multiple FTE and were very sensitive to what loads they would fire with. The rounds that couldn't be fired in the benelli's fired without an issue in the Mossberg 930 autoloader. The first FTE occured during the last station. I could tell that the gun was extremely dirty and hot. A little gun oil would have likely fixed the problem temporarily but I didn't have any with me so I grabbed a handful of snow, pulled the bolt back and threw it in :twisted: . After the snow it fired the last station without a hiccup for both of us using the Mossberg. Thought I would share my issue with everyone else here.
  19. tgw

    tgw .22LR

    Messages:
    33
    Two Questions

    First question regards the Nordic barrel clamp. Unless I really tighten the two allen bolts the clamp tends to walk when I fire 25 rounds or so. Is there something I could apply to the barrel or magazine extension that would increase the friction between the two metal surfaces and the clamp?

    The second question involves not being able to load the full number of shells. Sometimes after reassembly after cleaning, only four rounds will fit so the follower is hanging up in the tube for some reason. If I remove the magazine extension cap and reattach, that solves the problem. I am wondering why this is? What I do now is after reassembly is to load the magazine to make sure the proper number of shells will go in. Luckily it is easy to unload after checking by using the bolt release button.
  20. reeseman67

    reeseman67 .223

    Messages:
    116
    How much lubrication do fellow 930 SPX users recommend, and

    Hey guys, just got my BEAUTIFUL NEW SPX YESTERDAY!!!!! (YEAAAA, took a year but I got it!) Took it apart (which couldnt be simpler!) and I have it down to it's components, I'm wondering how much Rem-Oil or Hoppes lube I should use and where all is recommended for ideal and reliable (!!!) functioning, as this is my first semi-auto SHOTGUN. I know where I THINK it should go (moving parts, parts that touch others, etc), but wanna know if there is a particular amount, or placement of lube that this shotty might be prefferential to. I'll leave it apart once I'm done CLEANING (they DO COME DIRTY! But maybe thats a good sign that theyre testing them more now, and why I got 'lucky' with no visible problems with sights and stuff?). I thought I had a crooked mag extension tube, but it was just the angle and the way they screw on. Prob gonna replace it w/a Nordic, but if it works reliably as it does in testing shells going in and out so far its good! I'm gonna put the Aimpro rail on first as it is SO EASY TO DISSASEMBLE, as it just slides on(it is nice though that there is finally a forward sling mount till I get the rail and use a M.I. forward sling adapter, man I'm so glad I took the plunge! Thanks for any info current 930 SPX users can help me figure out how much and in what locale this beauty likes to be wet, LOL! Thanks,
    Stephen :D :D :D

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