Mack1207 Posted June 28, 2013 Share Posted June 28, 2013 I have a Mossberg 930 JM pro. So I would like to start of with I have checked the ultimate 930 thread and I think I have a slightly different issue. I thought it was a "regular" feed stop malfunction that could be corrected by spring length adjustment. I bought a spare mag tube spring and tried varied lengths from 14" past the tube extension down to 7" past the tube. Nothing worked. I then noticed that when a shell is inserted (standard 2 3/4" 1 oz and 1 1/8 oz bird shot) the head of the shell is loading about an 1/8" inside the tube instead of flush (as a baseline I also put the same shells in a Benelli M1014, a Mossberg 500 and a Rock Island M5). This results (I'm not sure how directly) in my malfunctions. The exactly description of my malfunctions are as follow: bolt goes home to the breech without loading shell, will load and extract/eject shell when round inserted into the ejection port for loading but then will only sometimes reload shotgun from mag tube. When I have shells in the magtube and the bolt to the rear I press the bolt catch and it will sometimes load two shells into the riser jamming the gun and other times load one shell onto the riser (not the breech) and kick one out the bottom of the loading port. I did call Mossberg (this is a brand new gun) and they told me I could send it in with a mailing address and a description of the issue but they don't know how long it will take to fix. This is my only personal semi auto gun and I use it for three gun (or would if I could get it running). Thanks in advance! Link to comment Share on other sites More sharing options...
GunCat Posted June 28, 2013 Share Posted June 28, 2013 Can you see or feel a gap between the end of the magazine tube and the receiver that would allow the shell rim to hang up at that 1/8" in spot? Link to comment Share on other sites More sharing options...
mpom Posted June 28, 2013 Share Posted June 28, 2013 Is the shell rim which is 1/8" inside tube not actually stopped by the shell stop? Link to comment Share on other sites More sharing options...
Mack1207 Posted June 29, 2013 Author Share Posted June 29, 2013 Hmm I will look when I get home tomorrow and post some pictures. Link to comment Share on other sites More sharing options...
LikesToShoot Posted June 29, 2013 Share Posted June 29, 2013 Here's a wild thought, probably not going to help but take the gun apart and make sure the mag tube is screwed all the way into the receiver. Maybe it's not down all the way and the rim of the shell is catching on an exposed thread in the receiver. Link to comment Share on other sites More sharing options...
GeorgeD Posted June 30, 2013 Share Posted June 30, 2013 This sounds like the same issue I was having with my 930. If I'm following your description right, the gun cycles but does not feed out of the magazine? Somehow, someway my shell stop bent not allowing shells to feed from the tube. I removed my shell stop and trimmed it down so not as much was in contact with the back of the shell in the mag. I filed quite a bit off then sanded the edge smooth, now it allows the shells to feed out of the tube. Now I just need to track down a new shell stop for a more permanent solution. Good luck, George Link to comment Share on other sites More sharing options...
Mack1207 Posted July 1, 2013 Author Share Posted July 1, 2013 http://www.brownells.com/.aspx/lid=15831/GunTechdetail/Fixing-A-Mossberg-930-Feed-From-The-Tube-Problem So I think this may be the issue, I'm going to try this and I'll report to y'all. Thanks for for the idea George. I feel like this is a fairly common issue. Link to comment Share on other sites More sharing options...
mpom Posted July 1, 2013 Share Posted July 1, 2013 the shell stop looks like a casting, with none to minimal machining, so pretty rough. polished mine as well for smoother function, also broke edge on side facing thumb pushing shells in, and corners. matches the welded up lifter in being digit friendly! Link to comment Share on other sites More sharing options...
Thecelt Posted July 1, 2013 Share Posted July 1, 2013 its a shame to have to take things apart and polish them to get them to work the way they should from the factory..... BUT considering this gun is half the cost of most of its competitors if having to do some polishing on our own to get them to function better is the worst of it then i say its still a bargain. I havent had this issue with mine(hope i dont jinx myself now), but i think im going to polish this part as well as a couple others just for good measure. thanks for posting that link as its very helpful! Link to comment Share on other sites More sharing options...
Twoyellowlabs Posted July 8, 2013 Share Posted July 8, 2013 Sounds like several people are having the same issues. You might want to call one of the local experts like Taran or Salient and see what it would cost to get them to do the work on your JMP as they do to Benellis. One is in Simi Valley and the other one is in Ventura. Might cost you a few bucks but at least you don't have to worry about if you are gonna miss the whole season waiting on a factory to respond. Link to comment Share on other sites More sharing options...
thegunnerd Posted July 8, 2013 Share Posted July 8, 2013 I had a similar issue with mine, end all was , I now shoot a benelli m2 Link to comment Share on other sites More sharing options...
Mack1207 Posted July 8, 2013 Author Share Posted July 8, 2013 Haha Thegunnerd... If I was allowed a second shotgun I wouldn't worry about it but personally I prefer "rack pt". Twoyellowlabs: what's the best way to contact them/wait times? I'm sure they are pretty busy most of the time. I may go that route depending on that link I posted above (whether I ever get time to actually do that) Link to comment Share on other sites More sharing options...
Twoyellowlabs Posted July 8, 2013 Share Posted July 8, 2013 (edited) Salient and Taran both have their contact info on their sites. Taran now has a website Taran Tactical Innovations. He is in Simi Valley. I believe your turnaround time would be quicker with Taran. Plus if you call him, he might offer you a fix over the phone. Dudes been shooting forever. Edited July 9, 2013 by Twoyellowlabs Link to comment Share on other sites More sharing options...
thegunnerd Posted July 9, 2013 Share Posted July 9, 2013 Haha Thegunnerd... If I was allowed a second shotgun I wouldn't worry about it but personally I prefer "rack pt". Twoyellowlabs: what's the best way to contact them/wait times? I'm sure they are pretty busy most of the time. I may go that route depending on that link I posted above (whether I ever get time to actually do that) Also just to let you know i sent my 930 to mossberg 2x and they still didn't fix the problem, i was lucky enough to , at that time, be having a gun built by shay akai and i had him fix the shell stop, which solved my problem ....ish. But i wouldn't have trusted the gun with my life , so i won't run it in competition. simple as that for me Link to comment Share on other sites More sharing options...
Twoyellowlabs Posted July 11, 2013 Share Posted July 11, 2013 So did you get the problem fixed Mack? Sounds like anyone specializing in smithing JM930's could build quite the business. Wonder if www.fixyourbrokenJM930.com domain name is available? Not to make light of your situation but it sounds like you are not the only one with the issues. Hope it all works out. Link to comment Share on other sites More sharing options...
thegunnerd Posted July 11, 2013 Share Posted July 11, 2013 HAHAHA ^^^ actually laughed out loud on that one. They're so hit or miss as guns go . My problem was never really fixed , and i wasn't going to go gun hunting for one that worked when i could barely find one. Benelli m2 to the rescue or if you can find a versamax -almost any versamax - run those. A close second the FN SLP . Yes, they cost more then the JM Pro, but , if you look for an older /used m2 or m1 . Maybe a versamax field . There are many options Link to comment Share on other sites More sharing options...
Twoyellowlabs Posted July 11, 2013 Share Posted July 11, 2013 I do see field grade Benelli M2's on Calguns quite regularly for around 11-1200 dollar range. Pretty good option if you want to just add an extension and go. TTI will do a complete workover and turn it into one of his competition guns for less than a grand. 2200 is still cheaper than getting a gun built by Salient for 3K. At least with the field grade M2, for less than a hundred bucks for an extension, you can shoot matches and turn it into a race gun later when the budget allows. Link to comment Share on other sites More sharing options...
thegunnerd Posted July 11, 2013 Share Posted July 11, 2013 That is exactly what I did ^^ . I just recently was able to fully upgrade it , but with a mag tube and little else you're good to go for a match. Link to comment Share on other sites More sharing options...
BobS761 Posted July 12, 2013 Share Posted July 12, 2013 Mine hasn't run 100% since day one. I'm not well versed or experienced with sasg, so I chalked it up to break in period. My first 3 Gun match it totally took a dump. Mag spring bound up in tube. But today it did something completely new. I ran an entire box of shells with not one malfunction. Here's what I did. Replaced mag spring with real Nordic spring, gas system run dry and wet bolt. But here's what is interesting, with AA 1300 fps loads, it would only run 3 in the tube. Any more and it would double feed. Feeling pretty discouraged, I tried some Nobel high brass 1300fps shells and suddenly it runs like a top, loaded to capacity. Is it fixed? I really don't know. Maybe mine just likes high brass, or the stars briefly aligned, or a butterfly farted in China. I'm probably at around 300 rounds, too many of them bolt action. Keeping my fingers crossed. Link to comment Share on other sites More sharing options...
thegunnerd Posted July 12, 2013 Share Posted July 12, 2013 I replaced my spring with a nordic as well, cut it to the proper length according to them. I still had issues. I hope yours get resolved , but i was never able to. I hate gun hunting for one that works. It makes me doubt the platform altogether and you don't want to doubt any of your guns , at least i don't Link to comment Share on other sites More sharing options...
BobS761 Posted July 12, 2013 Share Posted July 12, 2013 I replaced my spring with a nordic as well, cut it to the proper length according to them. I still had issues. I hope yours get resolved , but i was never able to. I hate gun hunting for one that works. It makes me doubt the platform altogether and you don't want to doubt any of your guns , at least i don't I agree, but I'm stuck with it for a while anyway. But when it works I really like how it shoots and points. Link to comment Share on other sites More sharing options...
Mack1207 Posted July 12, 2013 Author Share Posted July 12, 2013 I replaced my spring with a Nordic as well and cut it to length, I haven't attempted high brass which I may have to do. Hmm. This weekend I will actually have time to do the mod from that link above... I'll report my findings on the effectiveness! I really hope it helps because I also don't like playing this game with finding a gun that works out of the box Link to comment Share on other sites More sharing options...
Twoyellowlabs Posted July 12, 2013 Share Posted July 12, 2013 Thanks for the update Mack1207 and let us know how it works out. I shoot with several guys who have 930's. Will pass this information off to them as well when you give us the update. Link to comment Share on other sites More sharing options...
BobS761 Posted July 12, 2013 Share Posted July 12, 2013 I replaced my spring with a Nordic as well and cut it to length, I haven't attempted high brass which I may have to do. Hmm. This weekend I will actually have time to do the mod from that link above... I'll report my findings on the effectiveness! I really hope it helps because I also don't like playing this game with finding a gun that works out of the box Don't forget to put a small bend at each end of the spring, so it does not gouge the cap or follower. Link to comment Share on other sites More sharing options...
Thecelt Posted July 13, 2013 Share Posted July 13, 2013 If I can get the time this weekend I'm going polish up the shell stop this weekend although I won't get to test it for a few more weekends. Link to comment Share on other sites More sharing options...
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