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Mossberg 930 Autoloader Troubleshooting

Hi all,

Did a lot of googling trying to find a solution to the issue i'm having. I couldn't find anything with my exact problem, but this forum seemed to have the most helpful responses with other problems people had.

Basically, I bought the shotgun from used last week and I think I bought their problem. The gun ejects and chambers shells just fine, but it will not reset the hammer. A new shell will be fully chambered with the charging handle all the way forward, but it won't fire. Initially I thought it was probably because the piston/bolt were probably dirty and that was preventing the slide from sliding back far enough. However, as you'll see from the video I recorded, when I only fire one shell, the slide will lock open. Which means it has enough force to reset the hammer, but for some reason when it is loading another round, it fails to reset the hammer.


I'm stumped. Any ideas how to fix this?
 
Look at the hammer spring to see if the small metal cup is on the top of the spring. When the gun cycles it is supposed to reset the hammer and spring for the next shot but without the cup the spring slides off the hammer to the side and when the trigger is pulled nothing happens. Its a small piece that might have fallen off during cleaning. Good Luck.
 
Thanks for all the replies. I tried the magnum rounds with the same results. I showed the video to a local gunsmith and he immediately identified it as a broken sear. I contacted the former owner and he made it right. He replaced the broken sear with the sear off his new Mossberg JM. It runs beautifully now!
 
A potential solution for anyone having cycling issues with weaker ammo, particularly Walmart Winchester Universal 100 round value packs...

PROBLEM:
I have a 930 SPX with thousands of rounds through that simply wouldn't cycle Winchester Universal and Super-X. Cheap Federal heavy target loads over 1250 fps work fine. It would mostly extract spent shells, but wouldn't pull them far enough back to eject. A new shell would simultaneously be lifted from the tube, and the assembly would bind. Sometimes the extractor claw would slip off the rim of the shell.

REMEDIES ATTEMPTED:
The gun's gone back to Mossberg twice, with zero resolution. They replaced the lifter, shot some ammo through it, and dinged it up badly. Replaced the extractor. It still barfs on Winchester Universal.

Verified that the gas port holes were correctly sized and clean, cleaned the gun according to Mossberg. Cleaning the piston assembly helped some, but this gun has had trouble with Universal since day 1.

Suspected that the chamber was rough/tight, polished with 0000 steel wool on a stick, as well as Flitz.

SOLUTION:
Finally noticed that the chamber had a gray/black discoloration that wouldn't come off, no matter how hard I scrubbed. Upon closer inspection, it appeared to be parkerizing of the same shade as the exterior of the barrel, now well polished from the earlier attempts to remedy.

A two-armed brake cylinder hone was procured from Amazon: http://www.amazon.com/gp/product/B002INVEUM/

Ample oil was applied, and the drill was run at moderate speed, never stopping in the same spot, for about 30 seconds. Chamber was then wiped out and cleaned. Chamber is now shiny, with no black buildup/discoloration.

Gun now functions with Winchester Universal.

Takeaway: If you've tried everything else, and your gun still doesn't work with low brass loads, maybe a chamber honing is in order. I don't know if mine was cut undersized, had parkerizing (incorrectly?) applied to the chamber, or was maybe rough and eccentric, but the brake cylinder hone resolved my issues definitively.
 
armdude2000 said:
Hi all,

Did a lot of googling trying to find a solution to the issue i'm having. I couldn't find anything with my exact problem, but this forum seemed to have the most helpful responses with other problems people had.

Basically, I bought the shotgun from used last week and I think I bought their problem. The gun ejects and chambers shells just fine, but it will not reset the hammer. A new shell will be fully chambered with the charging handle all the way forward, but it won't fire. Initially I thought it was probably because the piston/bolt were probably dirty and that was preventing the slide from sliding back far enough. However, as you'll see from the video I recorded, when I only fire one shell, the slide will lock open. Which means it has enough force to reset the hammer, but for some reason when it is loading another round, it fails to reset the hammer.


I'm stumped. Any ideas how to fix this?
Click to expand...
I have the same exact problem. Brand new moss berg 930. Only 25 shells through it. Can't get the hammer to cycle, loaded or not. I removed the trigger according to the Mossberg guide, didn't really mess with it except for cleaning some gunk off from the factory.
 
Rehabber said:
Look at the hammer spring to see if the small metal cup is on the top of the spring. When the gun cycles it is supposed to reset the hammer and spring for the next shot but without the cup the spring slides off the hammer to the side and when the trigger is pulled nothing happens. Its a small piece that might have fallen off during cleaning. Good Luck.
Click to expand...

Is there a picture or good diagram that would show what you are talking about? I can pull the trigger assembly out, and wouldn't know what the heck you are talking about...
 
reeseman67 said:
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
Click to expand...

I don't leave too much rem oil on it. I put a lot on the bolt, piston assembly and pretty much the entire gun while I'm cleaning it but I wipe most of it off when I'm done. Excessive lubrication burns up and turns into a mess when you shoot. My 930's internals will run almost completely dry. When you take your piston assembly over the magazine tube apart, you'll notice that's where most of the mess is going to be. I wipe it with a patch from shirts I cut up and smooth the spot that is in direct contact with the gas ports with sandpaper. You'll see what I mean when you take the barrel off. It's where the retaining ring rests over the magazine. USE THE SANDPAPER LIGHTLY! No need to strip the finish, just twist it around the tube a bit. If you don't keep that smooth and clean, I could see that causing some malfunctions. It's completely covered by the handguard so I don't have an issue with the finish being scratched up a bit. I oil it before putting everything back together but I don't think it can rust because most Mossberg receivers (and I assume also the magazine tubes) are aluminum.

What do you intend to mount on your handguard? I've considered the railed handguards because they're awesome but I only need one rail. I have a Streamlight 69906 rail mount that goes on between the magazine tube and handguard. It's a mil spec piece of steel with a polymer rail riveted on to it. The rail overlaps the handguard and can be position on either side of the gun or on the bottom. I did a review of it a few years ago on the shotgun world forum and I'm still using it. I love it. It adds no time to disassembly which is one of my favorite things about it.
http://www.shotgunworld.com/bbs/viewtopic.php?f=7&t=321647

As for sling mounts, I got a set of grovtech mounts that replace the stud up front and mount on the back. I put my rear mount on the side and I like the way it hangs. $5 for the set.
http://mossbergowners.com/forum/index.php?threads/mossberg-930-combat-sling-mounts.12164/
 
My trigger will not reset. I've read everything I can, and have pulled the danged thing apparent at least three times. Any secrets out there not listed here?


Sent from my iPad using Tapatalk
 
itr2yhide said:
My trigger will not reset. I've read everything I can, and have pulled the danged thing apparent at least three times. Any secrets out there not listed here?


Sent from my iPad using Tapatalk
Click to expand...

Make sure the hollow pins / sleeves are both in the trigger assembly. The sleeves are what the actual pins that hold the trigger assembly in slide through.
 
Ok so here is where I'm at this is my second 930 first one never had a problem new one on cycle 3" loads with any regularity action come back extractor releases but she'll do a not kick out can shoot 2 3/4 7.5 3 dram all day but not 3" 1 1/8 number 3 at 1560 fps also noticed some heavy marking in the chamber will post pick this gun is still under warranty should of I try polishing or just return ImageUploadedByTapatalk1416776148.742982.jpgImageUploadedByTapatalk1416776168.826128.jpgImageUploadedByTapatalk1416776193.758299.jpg
 
Those are tool marks, I do not think these are causing your issues.. The rounds sticking in your chamber can be due to many various issues. I polished my chamber and forcing cone. This seems to have taken care of many of the issues I faced early on with my 930. The other issue to look for is a cracked pusher assembly (The two pronged black plastic doohickie that pushes on the bolt). One other thing to check is the gas spring located in front of the piston. Make sure it is not scaring up the magazine tube on assembly / dis-assembly. If so, sent the weapon to Mossberg for repair.
 
Pusher is good only about 75round through this one mag tube looks good going to try some different lube and polishing hard to see in crappy photos but those marks are pretty deep and did not start with them I was think follower or elevator possibly sticking as extractor releases but shell does not eject it's random so it hard to catch it to see what's truly going on is getting colder here so I think it may be a cold weather problem
 
In order to run in cold weather, you will need a very light oil and be sure there is not a lot of it. I recommend placing oil on the rings of the piston, lock up recess where the bolt locks into the barrel, and between the bolt body and carrier. Once oil is applied, wipe off the excess with a microfiber towel (I make one pass and move on). The marks on the barrel in the pics are most likely tool marks of some type. Nothing in that area twists.
 
Thanks mike I used frog lube but don't think I got it hot enough when I applied it never had these issues with my old 930 but it was used when I got it
 
Well had this apart relubed even removed and and checked spring in stock found no problem why did I ever sell my old 930 and buy a new one 2 3/4 have never had a failure 3" either bolt cycles and no shell have to cock it by hand or she'll won't eject load three more and next round is flawless as fast as you can pull the trigger have to say I'm really loosing faith in mossberg at this point what do you use to polish your chamber although I have issues going this far with a gun that's still under warranty
 
I am a newbie to this Forum and appreciate being added. I have owned a Mossberg 590A1 which I really like and decided to add a 930. I took delivery last week from my FFL after ordering from a reputable online store. When I got it home I took it down to my workbench to break it down and thorougly clean it. When I pulled the bolt back to lock it I immediately heard a rattle. I shook the gun a bit and a small L-shaped piece of metal fell out of the loading port onto the workbench. It is a part of the ejection mechanism. I can't call Mossberg on a Saturday and will have to wait until Monday. Just curious if anyone else has had this problem. If this has been answered elsewhere, I apologize as I am new to this forum and haven't had a chance to go through the posts. Thanks for your help.
 
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