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Mossberg 590 FLEX: Thoughts & Questions

Greetings ladies and gentlemen. This is my first post.

I bought my first shotgun today. I picked up a Mossberg 590 FLEX 12 gauge shotgun at a Bass Pro Shop in the KC MO area. I wanted a flexible, inexpensive sport/target/home defense weapon that my wife would enjoy shooting with me. I wanted something "tacti-cool" that would be fun to upgrade and tweak on the weekends, etc. I have pals who are retired police and they all recommended the Mossberg 590 Flex, so after some basic Internet research, I picked one up.

I have mixed feelings thus far.

As soon as I got the 590 FLEX shotgun home, I opened the Mossberg box and experimented with those sexy FLEX components. I removed the UTG six-position stock. A bit sticky at first, but overall well built. Kind of an interesting concept. TLS parts seem pretty cool to me.

Then I moved on to removing the forend. This is where my faith in O.F. Mossberg & Sons declined quickly.

I removed the FLEX forend with little issue. But as I was re-attaching the forend grip the damn thing broke on me. Pop.

The forend's thumb release button, spring, and a metal cam popped out all over my living room floor. Took me and my wife 30+ minutes to find them on my concrete floor.

Simple to fix, right? Not really. I was able to determine the placement of said parts (pretty sure they can only attach one way actually - kind of a no-brainer, really), but I can't for the life of me get the thumb release button to re-seat properly into the forend. I'm either missing yet another (super small) part, or its just plain busted. Great. Brand new. Never been shot. Broken parts. I spent weeks explaining to my wife that Mossberg was ad dependable company and brand. I'm eating "claim chowder" now.


What should I do?

Contact Bass Pro Shop? Get a repair/replacement/exchange/refund?

Contact Mossberg?

Thank you ladies and gentlemen for your time. Looking forward to sharing with the community. Ill be posting more questions regarding the 590 FLEX soon.
 
Welcome aboard and we're sorry to see you're having issues.

I would definitely suggest taking the shotgun back into BassPro for an exchange or refund, whichever you prefer. It will be a lot easier/faster to deal with them than with the manufacturer. Mossberg should be your second option if BassPro fails to satisfy your needs. There are many members here with Flex models who've had no issues and this is the first component failure we have seen posted. There is usually a bad apple in every bunch, but I wouldn't expect you'd experience the same issue with a different Flex shotgun if you decide to go that route. Keep us posted on your progress and if it comes down to a need to reach out to Mossberg we have a couple direct contacts that should be able to help...
 
Update:

Bass Pro would not return or exchange the gun ("All sales final"). They want to send it back to Mossberg. Had the gun literally 5 minutes and its already under a warranty repair? Not cool.

So I called Mossberg direct. Great people. Sending me for end parts - no questions asked. I think I can repair it myself. They didnt have an exploded view to share with me, which I found odd though. If I could just SEE a Mossberg 590 FLEX close up, I could use it as a reference (to see if I am missing a part, or otherwise attaching the thumb clip wrong, etc)

More news as it happens...
 
Damn, that really sucks about BassPro.

Guess they don't feel they need any return business. Oh well, glad to see Mossberg is taking care of you. As far as the new assembly goes you might send member @stigmata a PM requesting some assistance. He was one of the first on the forum with a FLEX model and he's sort of our FLEX system guru. I'm sure he wouldn't mind helping you out...
 
Don't mind at all..... I'm still here, just working a lot and not much gun time for me as of late, but if I can be of some help just fire away.
I actually removed my flex forend for a standard cob style for now, but will eventually go back to the flex one later.
As for the button on the forend to me it dose seem rather weak and cheap but I have never had a problem with the many removals of it from time to time.
I can check it out tomorrow and post what I find and see if it comes apart in some way??
 
Hi Stigmata

Thanks for the info and assistance. Much appreciated, sir.

I'd be curious to see how the thumb release is connected to your 590 FLEX. Can you take a few close-up pics? I went to a couple area stores to compare forends with, but they didn't have a 590 FLEX in stock to look at.

I have parts on the way from the Mossberg mothership. I hope they understood my telephone request. I have the gut feeling they are sending me another forened grip and not the actual mount/thumb release itself, but I won't know until it arrives next week.

Thanks again
 
Looks to have a roll pin holding the button in place.....

Sorry for the delay in the pics.


Its in a channel with a pin thru the middle of the button


Another

 
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Perfect shots. Thanks!

This was exactly what the doctor ordered. Those tight, close-up detail shots of the pin head and spring are what I was most curious about.

I wonder if I have all the parts. I have the grooved plastic/composite thumb button, a metal pin (more like a piston or a cam), and a spring that surrounds the cam. The spring and cam clearly fit inside the thumb release button. No-brainer there.

By the looks of your pictures (specifially the first photo), I am indeed missing another (very) small pin ("roll pin"?) that inserts laterally to the other parts (i.e it holds the other three parts in place). I see a tiny hole and wondered if it should be housing another pin or not.

If this is my missing pin - I suspect it is - then this itty-bitty pin was (A) missing from manufacturing/assembly process, or (2) popped-out when I opened the retail box and is now orphaned on my living room floor, but sweet Jesus it's microscopic. No chance of finding it now. Its smaller than a wrist watch pin. I have concrete floors, and that little guy could have rolled a long way (and subsequently been kicked, vacuumed-up, etc)

I'm not home right now. Ill head home later and compare/contrast your pics to my shotty.

More info to follow. Thanks again. You are more help than my KC MO Bass Pro Shop. They are sending you a consulting paycheck, right? ;0)
 
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Update:

I received a new, replacement forehand action slide assembly from Mossberg. It contains the molded plastic slide tube, (2) rails and of course, a U-pin, the grip release button. This is a single, molded component. The action slide tube is one piece, not multiple pieces like other (non-FLEX) shotguns. There is not end nut, etc.

Here's the weird part: It appears that my original FLEX 590 shotgun parts are indeed intact. It doesn't appear that I'm missing any parts or pins as originally thought. My only guess is that the hole that the release thumb lever cam/spring fits into must have not been molded/tapped/machined properly during assembly and thus my cam/spring won't fit properly. Just a guess but its all I can muster up.

My previous pictures posted above show what appeared to be differences between Stigmata's FLEX 590 and my FLEX 590. It looked to me like I was probably missing a pin, but on closer inspection of the replacement assembly that Mossberg just sent me, the particular hole in question does NOT contain any pins or cams. Our pictures don't have great lighting so it was hard to tell what this tiny hole was use for.

Regardless, I have a new assembly ready to install. Thanks, Mossberg. Couldn't be happier with customer service and quick turn around.

It appears to me that I will need to tear-down the shotgun completely to replace the action slide assembly. Looks like I will need to remove the barrel, trigger assembly & pin, and three internal components (bolt carrier plate and two rails).

I have seen a few videos on how to disassemble a standard Mossberg 590 shotgun. Is the FLEX series any different? Please advise if you are aware of any "gotchas". Any additional insight or information is greatly appreciated.

I found this video (below). Procedure looks fairly straightforward. But admittedly, I haven't never disassembled a shotgun before.

I'm going to give 'er try.

More news at 11.

 
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From my limited understanding the receiver internals are all the same, the only difference with the Flex is the TLS component on the back of the receiver and how the action tube interfaces with the fore end. Take down is pretty much the same except for those two factors as far as I know. I was very close to getting myself a 500 Flex 7+1 in Coyote Tan, beautiful gun, but chose a 590A1 instead. Good luck and keep us posted!
 
Problem solved.

I replaced my action slide assembly with the new one from Mossberg as instructed in the video above. Very simple. Works great now.

Thanks.
 
Glad you got your issue fixed boomstick. Sorry for the late reply but I moved to Austin at the beginning of July and just got fully settled last month and now I'm on here a bit more. If you need anymore help with anything just pm me.
Just got me a std buttstock for the flex to replace the 6 position stock.
Like to have options if needed. Lol.
 
I know that this thread is a couple of months old but for any newbie reading it let me just add an important point.
Any NEW gun should ALWAYS be disassembled and thoroughly cleaned before firing.
After reading these sentences

"It appears to me that I will need to tear-down the shotgun completely to replace the action slide assembly. Looks like I will need to remove the barrel, trigger assembly & pin, and three internal components (bolt carrier plate and two rails).

I have seen a few videos on how to disassemble a standard Mossberg 590 shotgun. Is the FLEX series any different? Please advise if you are aware of any "gotchas". Any additional insight or information is greatly appreciated."

I figured that I should put this out here.
 
How are you liking your gun now? Looks like I bought the same gun at the same place. Have you made any changes to it???
 
How are you liking your gun now? Looks like I bought the same gun at the same place. Have you made any changes to it???
If you need help with anything. Were always here. I'm on a bit less than I used to be (damn work) but I try to get on here at least every day or two.
If u need help just post away.
 
Hey fellas, I joined to specifically reply to this thread. I had the exact same issue with my release button. It shot across the room. I have the piston looking metal piece, the spring, & the button. Am I missing something? I can't get it to stay in. If Mossberg has to replace what is the turnaround time? Thank you all in advance for your help.
 
Same thing just happened to my 500 Flex tactical. I cannot find a replacement flex slide tube assembly anywhere. The standard one, sure, but not the flex version with the button.

They want me to send it in for repair, and I'd prefer to replace the part now so the shotgun is still functional while they repair the original part.

If anyone knows where I can buy this assembly pls LMK. Thanks.
 
Welcome Ulag.
Man it sux that ur having that forend issue with your new Flex.

As for replacement parts, i haven't seen any but I have seen the whole flex assy at Academy and Bass Pro before.
Usually only have one in stock the few times I did see them.

I can't say that I have ever had a problem with my flex forend b4 but it was a bit of work to get it on right but came off at the push of a button.
I have changed my forend out for a standard cob forend but it was just for preference not because I was having issues.
I haven't put the OEM forend back on but i am always changing stuff out on it and will get it back on there one day.

Hope u find what ur after and keep us posted too bud.
 
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