Mossberg 930

[justinvan]

Anybody have any experiance with the Mossberg 930, more than likely the spx, it seems to fill a void I seem to think needs filling. I knows not the best option out there but you cant deny it comes at an attractive price point and the reviews I have read have been far from bad.

[deadarrow]

Have had mine for a while now. Have yet to shoot it in a match but I plan to rectify that this saturday. The only thing I did to it was send the barrel out to have it reamed and threaded for choke tubes. The 18.5 inch cylander bore stock barrel is fine for home defence but for 3 gun it's just too much of a spread. Now I can change the pattern as needed. Have shot probly 300 or 400 rounds through it so far. Various types of shells from 3'' mag slugs to cheap winchester target loads. Never a hic-cup, cycled everything great. For the money you can't go wrong. I actually just purchaced the 930 field model also. Shot some trap sunday and right out of the box it was flawless. Plus I can use the same choke tubes for both of my 930's.

[rockcreek]

Don't let the price point fool you, the 930 will run with any auto out there. I have the field model, which I bought right when they came out, and have sold a bunch of them. I have put at least 10,000 rounds through mine. They will cycle just about anything from 1oz promo loads, to 3" buckshot without a hitch. Lots of barrels and accesories are available for them too. Like any gas gun, they do need to be cleaned regularly. I have found depending on the powder used, I can go between 300-600 rounds before the gas system gets too dirty to function.

[shooter115]

The new 930 JM Pro Series guns are selling like hot cakes to 3-gun shooters right now. I suspect there will be lots of feedback on them coming from the 3-gun circle over the next couple months.

[promod1385]

I couldnt wait for the JM Pro model so I picked up a 24" Turkey and added a Nordic tube and clamp (made some covers to fill in the ports). Been shooting it in Tac for 3gun. Its been a great shotgun. Only problem was with some older Remington pheasant loads. I am guessing they were a bit bulged because they prevented the gun from going in to battery. They did all however eject and go bang one I tapped on the bolt handle.

I would recommend it to anyone. If using for HD I would test it wtih 00buck and some slugs. I am guessing it will function just fine with this ammo.

[Payne]

I just picked up the 24" barrel 9+1 Mossberg JM 930 Pro last night. Took it out today and I must say, very impressed thus far. I can tell I need to look into the stock shims to get it fit to me, other than that it ran without a hitch. I will be trying slugs on Friday and taking it to the 3-gun at MG&F on Sat. as a backup to my M2 Benelli. I noticed that it loads easier than the Benelli but the mag spring feels a little less stiff. I just ordered a new one from Nordic for "just in case". I will be opening up the loading port a little just to make it smoother. I load weak hand and didn't feel the lifter fork touching my thumb at all, and getting it opened up a little will give thumb even more room. I don't think I will have time to stipple the grip and forarm before Sat.

If anyone wants to see it just look me up. If anyone needs a shotgun for the match, just bring ammo.

[Dave Timm]

We have been running them all last year. Of the three we got, 2 out of the 3 worked fine, the third needed some work to get up and running. Overall though, I am very impressed with this shotgun. We bought the 18.5" barrel version with the ghost rings sights or something like that. It wasn't our intended model but at the time it was that or ported turkey models that were a no go in Tac Optics class. There was no JM pro version at that time, but in essence we built up something very similar. After we ran them out of the box I started to build them up.

We did the following on all of ours:
-Added the non ported 24" barrel (which is available from Mossberg but you have to make sure you order the non ported version)
-Ditched the ghost ring sights/optic rail and just used some vent rip fiber optic sights, really happy had no prob hitting slugs at 100 yards
-Nordic mag tube (I think +5 , ends flush with barrel with small extension)

On mine I added some extra touches:
-Stippled the forearm and pistol grip
-Molded in a 2 shell caddy on the forearm for emergency reloads/slugs etc.
-Opened the loading port in front to add in reloads and to prevent my thumb getting stuck
-Beveled the edges of the loading port to aid in loading and remove the sharp edges
-Smoothed the edges of the lifter fork to take away the sharp edges and polish it

Long story short, my shotgun runs and I have been very impressed with it. I do have a Benelli M2 at a shop getting built up but I have never gone to a match and felt worried about the performance of my Mossberg once we figured out what makes it run. For us we had some problems initially with low brass ammo but that has seem to improve after a longer then expected break in period. I also find that cleaning the piston, and also magtube where the piston cycles, helps a lot. The crud can really cake on there so a little scotch bright pad helped, after cleaning I ran the piston with some lube and it runs great for me.

If you do get one buy a variety of ammo and see what it runs. Ours run great with the higher DRAM ammo but with a good stance everything seems to run ok. I guess on that point if you don't have a solid stance it can misfeed so give the action that solid foundation of a good shooting stance and all should be good.

I echo Payne, if anyone wants to check mine out at the match this saturday please stop me, Im the husky fella wearing a Huldra shirt.
Dave

[Dave Timm]

My opinion is changing slightly, at the last 3 gun match on the last stage mine turned into a single shot. Im not sure why, my theories at this point is to low of power ammo or its dirty somewhere that I didn't clean that well before. I know several people who have them say they run on anything but before I was using higher brass ammo where as I just picked up some standard low brass target stuff. The weird thing is before the match I shot about 50 rounds in practice and it cycled fine, the first stages of the match were fine as well. Then the last stage, poof, and there went reliability. I threw all of the parts in my ultrasonic cleaner and I will head to the range this week and see if the piston was just dirty or what. I saw on the JM model they chromed the mag tube and piston so maybe there is something there.

This was the first time this shotgun has really let me down, Im hoping its a fluke but either way it will take a long time for me to trust it again. If anyone has had a similar experience or has any ideas please let me know. I did notice there were some burrs on the receiver inside, I smoothed those over and also cleaned up the bolt lock up tab as that was a little rough.

Anyone with info or experience I'd be all ears, likewise I'll let you know what I find out.
Thanks
Dave

[Payne]

Dave

First off, you had a great day of shooting. Sorry to see the last stage give the problems that it did.

I was paying attention to your weapon due to the fact the person that borrowed my Mossberg JM 930 Pro had problems also.

Your shotgun was perfect until the last stage. I did notice that for half of the match, the air was damp even when it wasn't raining. I had trouble keeping my hands dry. It looked to me like your shotgun would fire, cycle a new round into the chamber, then click without firing the new round. It almost appeared as if the bolt was not going completely into battery. I didn't get a chance to look at your ammo that you picked up off the ground to see if the primer was dented or not. I would rule out the ammo part of the equation, and go more toward rain/moisture related gunk build up. Seemed very weird.

I was watching yours because my 930 had some failures as well. Not unexpected because I had only run 25 rounds through it prior to the match. One thing I did notice when I got the shotgun was that the magazine spring seemed very soft, too soft actually. One of the malfunctions appears to have been caused by not enough magazine spring tension. Yesterday I replaced the stock spring with a Nordic Components spring cut to proper length. Shot 25 rounds of 3 Dram, 1 1/8 oz., 8 shot cheap Remington Gun Club loads and it worked perfectly.

Good luck on finding the cause of your malfunctions.

[Pinnacle]

Seems like a heck of a package for the $$$$. This is one that I would invest in the Shotgun Speedloaders for. There are things about this gun that make a lot of sense.

It is about time that the MFG's took the hint from the shooters that play the games that we all like to play.

[deadarrow]

Mine ran great saturday at the 3 gun match. Having choke tube options made it perfect. This was the first time using it in a match but it has several hundred rounds through it. Loading was smooth and no hic-ups at all.

[Dave Timm]

Thanks Payne, always enjoy shooting with you, you're a great shooter and ambassador to our sport.

Well I truly believe I have found the culprit. I spent some time researching my issue and thanks to great folks at shotgunworld.com and mossberg owners forum I learned a ton about the platform. The heart of the system, and part that needs the most attention, is the actual piston itself. The malfunction I had was the fired round would eject, new round would feed, the bolt would go forward, but the slide (the bottom part of the bolt assembly) would not go into battery and not lock up. What I learned that this malfunction is text book when the piston drags. When the piston drags it prevents the slide from locking forward and locking up.

I learned two things, one I had to adjust my piston spring, and two I had to remove the gas piston rings and clean the rings and under the rings on the piston. Cleaning the exterior of the piston alone was not good enough. Once I adjusted (centered is really a better term) the spring, which is in the barrel forward of the where the piston resides, the barrel went on much easier. If you feel friction when installing or removing the barrel, or find marks on the mag tube, your piston spring probably needs to be adjusted and centered. To adjust the piston spring, I used a deep well socket, 19mm, or you can use a dowel rod close to the same size as the mag tube. With the dowel/socket/rod, then use that to center the spring, you may see that it is not centered and one edge is exposed more then the other, not the circle within a circle so to speak. Again, once this was adjusted I was very impressed with the difference it made on the reduction of friction on the barrel.

Then once I removed the two piston rings I found a lot of hard, baked on crud. I put all of the individual pieces in my cleaner. This worked somewhat but I still needed to scrape, pick, and brush off the parts. Once clean, I reassembled everything except of the fore arm. Here is where I really saw the difference. The piston should move pretty easily when everything is assembled and you pull down on the spacer. Likewise the piston should install and remove very easily. Mine was always very tight to install and remove and did not move easily on the mag tube. Now that it's clean it installs/removes very easily, practically falls out, and moves on the mag tube. It was also recommended to polish and smooth up the mag tube but aside from a good cleaning I have not polished that yet.

Judging by just how the gun feels on the bench I think I have found the issue was some needed adjustment and maintainence. I can't really blame the gun for that as I have put alot of flawless rounds through it previously. I am going to get to the range with a variety of ammunition from high brass high DRAM to the cheap stuff and test it out.

I can post some photos or maybe a video if anyone is interested, I'd be happy to share what I've learned so far. If this is it, I am still very impressed with this shotgun for the price. If the piston just needs some TLC a little more then I expected I am still perfectly ok with that and when it runs, it runs and shoots great for me.

Take care,
Dave

[Payne]

The Mossberg JM 930 has a chromed mag tube where the piston slides back and forth. I am hoping that this helps a little. I will have to have you educate me a little on the piston and the piston spring. I have used nothing but Benelli for several years and all this gas piston crap is confusing to me.

[Dave Timm]

I'd be happy to, its actually a pretty simple piston design. If this cures my issues Ill be very pleased and still impressed with the gun. Everything I have read and leanred seems to stem around the piston, once it gets dirty or causes drag then malfunctions will start to surface. If this gun needs a little more maintenance then others, for the price it still is hard to beat.

Im thinking about making a video once everything gets back up and running (optimistic) on 930 maintanence. All of the videos I found, a part was here, another there, not a complete video with all the info.

[Jackpine Savage]

Dave, a video of all that would be great and much appreciated.

I picked up a JM 8+1 a couple weeks ago. I stripped it down, cleaned and re-lubed it before I shot it. I've put about 4 boxes through it. I had one round fail to fire. I'm not sure if it was a light strike or a bad shell.