mossberg 930 ammo issue? shell stop issue? spring issue?

[breakingcontact]

Mossberg 930, ammo, shell stop or spring length? TL;DR (aka Readers Digest version) Remington ammo brass being dented. Is problem, too long of a mag spring, shell stop or just the ammo?

For the rest of the story read below...

I have a +2 Nordic extension and Nordic spring.

I have extensively searched the forum.

My gun simply wasn't picking up a round to chamber on the first round when cycling by hand most of the time, even when cycling hard it often would not release a round from the magazine tube.

So I removed the shell stop and lightly polished it to ensure it didn't have any burs or sharp spots on it. Reassembled gun and same issue. I then examined the shells I was chambering (when they would chamber). The Remington ammo I was using must have soft brass. After using the same round over and over it would go from picking up somewhat reliably when new to not picking up at all once I'd loaded it a few times. The brass actually had a dent in it from the shell stop.

By the time I'd cycled a round of Remington 5 times, it wouldn't release from the mag tube at all.

So I then figured I had too much spring in the magazine tube, 26" Nordic Spring. I cut another inch off the spring so I'm down to 25" now and it still is exhibiting the same problems. I really don't want to cut any more off the spring but perhaps it's still too long which is why the brass is being dented?

I finally switched ammo(should have tried first). With Federal, it loads from the mag tube every time. I cycled the same round 30 times and no hiccups.

So I said all that to ask this:

• should I just chalk it up to the ammo?
  
• should I try to modify/replace the shell stop so it is not denting the Remington brass?
  
• am I asking too much that the gun handles all brands well?
  
• am I asking too much from the ammo?
  
• Should I get another spring and cut it to be longer than the 25" I'm currently using? I believe I saw either Lazy Eyed Sniper or M24shooter say the ideal length was 25-28" (and that was for the +3 930 SPX) Mine is cycling 100% by hand now, including the last round which comes out with decent enough force it's just I'm kind of kicking myself for cutting it when the spring wasn't the problem.
  

Appreciate any input.

Edited July 3, 2013 by breakingcontact

[Nuke8401]

I believe the short length spec for the spring is 12" past the tube. Sounds like your is way long. Some, mine , are cut to 10" past the mag tube and work great. Cutting the spring to the short end of the spec improves hand cycling along with streaching the shell release spring which you must have had out when polishing the stop. Also, you have to cycle it hard, almost as hard as the gun cycles when firing. The shell stop moves indirectly from the bolt compressing the shell stop spring.

See "Mossberg 930 issues" thread for hand cycling.

Edited July 3, 2013 by Nuke8401

[mpom]

have you tried running the oem mag tube spring?

[breakingcontact]

My total spring length is 25 inches. The portion past the extension is 8 inches. I ordered a few extra springs and didn't know if mine should be longer.

I just tried running the OEM mag tube spring, it was better, but I still reached a point where the Remington ammo would not feed from the magazine.

So I definitely don't think the magazine spring is too long or strong. I did remove the shell stop and tried to smooth it with some fine steel wool, I am hesitant to take a file or dremel to it. There was a lot of grease under the shell stop lever so I cleaned that out and oiled it well.

Unless I'm missing something this leaves me with, "don't use Remington ammo", "don't chamber rounds more than once or twice" or I need to replace or work on the shell stop. I haven't stretched the spring yet as I was unsure if that would cause other issues.

I haven't shot this gun yet. I had a 930 SPX where the mag extension gave me fits so I am trying to make sure this one is good to go before I get frustrated at the range with it.

Edited July 4, 2013 by breakingcontact

[outerlimits]

benny built my 930 before the 930 JM came out. it has the exact same problem. still does, as a matter of fact. polished the shell stop and no difference. then, i found out it WAS the brass! i can get it to happen every time with dummy rounds from brownells, or wally world bulk pack shit. using AA's or STS it will feed every friggin' time. go figure, but all i shoot is AA's anyway.

[T Bacus]

So I said all that to ask this:

• should I just chalk it up to the ammo?
• should I try to modify/replace the shell stop so it is not denting the Remington brass?
• am I asking too much that the gun handles all brands well?
• am I asking too much from the ammo?
• Should I get another spring and cut it to be longer than the 25" I'm currently using? I believe I saw either Lazy Eyed Sniper or M24shooter say the ideal length was 25-28" (and that was for the +3 930 SPX) Mine is cycling 100% by hand now, including the last round which comes out with decent enough force it's just I'm kind of kicking myself for cutting it when the spring wasn't the problem.

Appreciate any input.

I read and re-read your post and I don't seem to see were you describe how the gun functions when shooting it. Have you shot it?

[breakingcontact]

I am kind of building my own as well. I liked my 930 SPX but the choate extension problems soured me on the whole gun. Was able to sell it for a nice price so wasn't too upset. Starting from scratch with a home defense model this time around. Like my setup so far. +2 MXT extension from Nordic with mag clamp and Streamlight on the side, red fiber optic front sight, velcro side saddle, GG&G sling mount. Need to replace the safety.

I don't want to mess up the gun mechanically so I will have to watch the ammo I use or more fairly, not rechamber ammo more than once or twice. I may consider stretching the shell stop spring but not until I can order some replacements in case it doesn't work right.

[breakingcontact]

Post#4. Haven't shot it yet.

I am kind of building my own as well. I liked my 930 SPX but the choate extension problems soured me on the whole gun. Was able to sell it for a nice price so wasn't too upset. Starting from scratch with a home defense model this time around. Like my setup so far. +2 MXT extension from Nordic with mag clamp and Streamlight on the side, red fiber optic front sight, velcro side saddle, GG&G sling mount. Need to replace the safety.

I don't want to mess up the gun mechanically so I will have to watch the ammo I use or more fairly, not rechamber ammo more than once or twice. I may consider stretching the shell stop spring but not until I can order some replacements in case it doesn't work right.

[mpom]

I would cycle the bolt slowly with the gun upside down, and look at the shell stop and rim of cartridge to see if shell stop retracts enough to let rim pass as bolt is retracted fully. Would compare movement of shell stop between the Remington and Federal brass. Is the Remington rim larger/wider than the Federal? See if pushing shell stop away from rim allows rim to pass. Perhaps front of shell stop, facing rim is rough and hanging on to rim, or part of shell stop blocking rim is too long and will not get out of way of rim. Shortening a tiny bit and polishing the end of that hook might be needed. Looks like a MIM casting that needs a little smoothing. Fine sandpaper on a flat file or a cratex on a dremel applied carefully should not hurt it, and has not hurt mine. I put a radius into the hook of the stop to match the curve of a shell rim. If section of shell stop contacting rim is smooth and flat with no burrs and mag spring not overly powerful, cannot understand how the Remington brass is getting dented, unless its unusually soft. Possible its ammo related, but I have cycled my dummy Brownell rounds dozens of times each without any issues, and ejected live ammo shows no signs of denting the rim.

Its possible the vibrations and recoil induced by live fire may allow proper feeding from the mag tube, but yes, the shotgun should still be capable of hand cycling, if only to unload it.

After all that, since Federal ammo has no issues even after 30 cycles, simplest thing is to stay away from the flavor of Remington that is having issues.

Edited July 4, 2013 by mpom

[breakingcontact]

Is the Remington rim larger/wider than the Federal? See if pushing shell stop away from rim allows rim to pass.

Perhaps front of shell stop, facing rim is rough and hanging on to rim, or part of shell stop blocking rim is too long and will not get out of way of rim. Shortening a tiny bit and polishing the end of that hook might be needed. Looks like a MIM casting that needs a little smoothing.

Possible its ammo related, but I have cycled my dummy Brownell rounds dozens of times each without any issues, and ejected live ammo shows no signs of denting the rim.

Its possible the vibrations and recoil induced by live fire may allow proper feeding from the mag tube, but yes, the shotgun should still be capable of hand cycling, if only to unload it.

After all that, since Federal ammo has no issues even after 30 cycles, simplest thing is to stay away from the flavor of Remington that is having issues.

Remington and Federal shells are same diameter.

I polished the front of the shell stop, but didn't want to work on it too much, it looking like a MIM and all.

My dummy rounds feed fine. A-Zoom snap caps, they are all scratched up, but not dented at all like the Remington brass. I haven't fired it yet. I am confident it will function fine once the first round is loaded as no other rounds are hard to load.

I've considered trying some other Remington shells I have. Perhaps it's just this box or this load. I don't know though, I had issues with Remington ammo before in a small pistol.

Thanks for the feedback.