Unfortunately for me, I purchased my rifle before I found this forum, had I know about all of the little nuances, who knows what I would of done. That being said, I've had it for a whole 3 days and have completely stripped it down (everything except for the trigger assy), cleaned it, studied it and have a few observations.
1) It's meant to be an entry level model that had a significant number of parts that are made in factories that have questionable QC practices.
2) The process of making the polymer parts in the 25 round magazine leaves a lot of mold flash, which seems to induce additional friction and inconsistent feeding of rounds.
3) Since I'm new to Mossberg, please excuse the ignorance and what is probably a painfully obvious statement, but the receiver, bolt and carrier assembly are all right off the 702 and Mossberg decided to cash in on the public's demand for military style rifles by simply designing a polymer shell and trigger mechanism around the 702 platform.
It's actually a cool little weapon that does have some potential, however, the execution in which it was put to market lacks considerably.
Personal observations:
a) Recoil buffer: Personally, I wouldn't have gone with such a hard compound on a piece that is designed to absorb all that energy, after every shot. It seems as if there have been a significant number complaints on them splitting in two, or simply breaking. Maybe a harder urethane than a PVC style polymer would have been a wiser choice. Who knows, maybe if I get something closer to what I'm thinking of I can make one to see if that works a little better.
b) 25 round magazine - I've read a LOT of posts that date back several years, and it seems as if Mossberg has made little progress in working out all the little kinks in the feeding of cartridges. I took the magazine apart and the little black piece that sits between the two springs (at least on my rifle) seems to move inconsistently because of mold flash. I filed it smooth and then in the areas I could reach, I used some 800 grit sand paper to polish it a little bit. After I got all of the major contact points cleaned up, I put some lube in both the feed channel and on the piece itself. It does move much more smoothly.
The top metal piece in the magazine was filled with some sort of nasty brown grease, which looked more like earwax, rather than a lube. I cleaned all that out and lightly coated it with my preferred lube. That seems to help with cartridge travel in that section.
Another thing I noticed, is that the top spring that mates with the red piece was installed backwards. In my experience with magazines of this type (AR's, AK's etc), the full loop goes towards the front goes to the front and the half loop/end, goes towards the back.
c) New, out of the box, the product need to be completely stripped and cleaned. I've worked with some filthy weapons before, some of which have been packed full of cosmoline for the past 80 years or so, and I have to say this thing was filthy. The bolt carriage face looked as if it had over 500 rounds on it already, the barrel was nasty and required a log soak with solvent, and after the solvent was removed, I ran a couple of patches soaked with CLP through, let it sit for awhile and the proceeded to run a bore snake through and then used a jag, until the patches came out clean (took over 15).
I'm hoping all of this will aid with FTE's, FTF's & FTL's, but I won't know until I get it out to the range. I mean it's a cool little rifle, and has quite a bit of potential, but I do have to question some of the design and manufacturing decisions made by Mossberg.
Just my 2 cents.