590A1 - Very Stiff Fore End (Not So With 590 Shockwave)

thegazelle

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Hi, quick question for everyone.

I recently bought a new 590A1 Marinecote - took it to my club Sunday and cycled some Score low recoil slugs on it. Previous to this, when I was at home, to check function, I ran six snap caps through it just to check out cycling, after initial inspection. Seemed OK.

I noticed after the first few shots, the fore end was very very stiff and and it wouldn't cycle (or so it seemed). The action release was already depressed and was spongy. The lifter was down but I was able to start manually releasing shells from the tube (using the little side springy end of the bar) while I was trying to figure out why the action was seemingly jammed. My friend was there and saw it and thought it was weird. Eventually with a very, very violent pull of the fore end (not great for my poor injured shoulder), it ejected the spent hull.

My friend and I looked at it and he said to me, did you take this thing apart and oil and lube it? I said no. I probably should have, but a bad habit I have for new guns is to visually inspect everything and only take it apart if there is an excessive amount of factory grease on it or that I noticed something awry. He suspected that all the parts were super dry and I need to go home and lube it.

I previously had a 590 Shockwave SPX and I never cleaned / lubed it out of the box since new and it cycled fine in the short lifetime that I had it and shot it.

I ended up taking the 590A1 apart last night - putting it back together was more of a pain, but I got it done - I super lubed the thing to the point where it was almost dripping Hoppes 9. Every piece that I removed aside from the magazine spring, follower and mag cap, I lubed - this is primarily action bars, bolt, the metal thing that sits on top of the bolt and connects with the fore end action bars, the lifter, those two goofy side bars, etc. Even a bit on the trigger assembly. I ran the same snap caps through it at home and it didn't seem like it was any smoother and in some cases, I noticed it was stiffer on some cycles.

Is this just a matter of use and continued cycling to loosen everything up? If it's the case, I can just run the fore end like a physio exercise daily. I am surprised if the lube ended up being the issue since for the 590 Shockwave, I never had these problems.
 
Depending on ammo... it could be the back of the chamber needs polishing where the brass of the shell makes contact. Wipe all that excess lube out to start with.
 
Depending on ammo... it could be the back of the chamber needs polishing where the brass of the shell makes contact. Wipe all that excess lube out to start with.
There was no lube that I saw at all when I disassembled it, which lends credence to what my buddy was saying. For a new gun, it was surprisingly dry. I have since greased like like crazy with Hoppes 9.
 
I would want to be trying other ammo types out first to try and isolate the issue. Shouldn't be an issue with a Mossberg pump of any kind, new or old.

Chamber polishing is a possibility as noted but I wouldn't want to jump to altering the gun if new. Shouldn't be happening at all, and could void the warranty/limit your options. When you say it's binding, that suggests there is an issue with the action bars, possibly incorrect assembly or damaged parts.

I've polished 870 Express chambers that needed them, but have also found (with Remingtons) that sometimes the cut-out (on the barrel) for the extractor is not positioned correctly and needs to be opened-up. Learned that polishing a chamber that didn't need polishing. lol
 
There was no lube that I saw at all when I disassembled it, which lends credence to what my buddy was saying. For a new gun, it was surprisingly dry. I have since greased like like crazy with Hoppes 9.
Hoppes #9 is an oil, and will run and drip, grease is a thicker product that will mostly stay where you put it unless things are really moving fast!

What Guntech is trying to tell you is that a "soaking wet with oil gun" is not what you want. Dry off the access oil. the finish of the parerkized finish of the 590A1 should absorb and hold some oil which will help for corrosion resistance, and there are a few places.

The other things people are suggesting is that sometimes with cheap low brass shells they can get stuck in the chamber after firing making them harder to extract and suggesting that the chamber might need to be polished a bit to help with that, but in your case it sounds like yours is stiff running snap caps or just cyling the action with the action release and no shells at all.

I don't find the 590A1's to be the smoothest pump actions to begin with, maybe yours is just a bit on the stiff side of that and has some rough spots or burrs that need to be worked out.

Here's a checklist with suggestions of where to polish, Grease and Oil.

https://thegunzone.com/how-to-slick-up-the-action-of-a-mossberg-590a1/
 
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Hoppes #9 is an oil, and will run and drip, grease is a thicker product that will mostly stay where you put it unless things are really moving fast!

What Guntech is trying to tell you is that a "soaking wet with oil gun" is not what you want. Dry off the access oil. the finish of the parerkized finish of the 590A1 should absorb and hold some oil which will help for corrosion resistance, and there are a few places.

The other things people are suggesting is that sometimes with cheap low brass shells they can get stuck in the chamber after firing making them harder to extract and suggesting that the chamber might need to be polished a bit to help with that, but in your case it sounds like yours is stiff running snap caps or just cyling the action with the action release and no shells at all.

I don't find the 590A1's to be the smoothest pump actions to begin with, maybe yours is just a bit on the stiff side of that.
Ok, I'll take it apart again tonight.

What do you suggest for grease? I have lithium grease here but if you recommend another product, let me know and I'll run over to Princess Auto.

I have Hoppes 9 here, Otis CLP, and G96 here - I have used most of those over the years to clean and lube... I am also not a handy or technical guy, so bear with my ignorance!
 
Spray parts with G96 and wipe off the excess... Grease on a pump shotgun really is not needed. Excess grease is even worse. Hoppes #9 is a solvent and very runny.

The title is mis leading... Hard ejection after firing sounds like the problem.
 
I like Superlube, it's handy for lot's of things from plumbing, auto battery terminals , guns etc..
https://www.amazon.ca/Super-Lube-21030-Synthetic-Grease/dp/B000XBH9HI/ref=sr_1_6?adgrpid=1360096113628811&dib=eyJ2IjoiMSJ9.wVzvSULi_XWIvtvaIJRes0CsUEkRVMWoN7jOK5HMfKYW7dodDc0Lwy4VSsYkaDSiBOff0NQc_mEikfqn9wVEvSZpa1Hlk5dYftUviYJqmpyHStrsB-vBI19GR3VPKLVbgsrRVyP3m0oa3oe250Im_JSAk82oY3j3i27xRa6a5CszNqlR4m65i6-hEo9pjAHl0KFNzi0Th95-onjK-5MpeEiQfnx9LcbEQ2rhE4qGlTX0-4n4CAV8w2SJU6g2P5A9WiS1gKw_APCyEMquE618o6iB5WeQkjnFW8STcuHPQ52uqeua1a1MAlhC2vNdJ4JXvCO10fC-uHQz0igIexCX2M6lLyIhadM3WvLXgQtKQrfzr96LPicSHTxTsJonOiAYQLMvaZbqX7ci8gU7bnx5FqcDSWEBnWbwjFPf6PWazQHbBEthYEQIrg3C7uj-zdUH.T_XRXdIb7vyCnvGXPRba3-5pwvSjEaTK63Ns2XNR51c&dib_tag=se&hvadid=85006546674655&hvbmt=bp&hvdev=c&hvlocphy=124660&hvnetw=s&hvqmt=p&hvtargid=kwd-85006176695718:loc-32&hydadcr=27524_14716878&keywords=clear+silicone+grease&mcid=ce42c43dffe53dc49ca434f0d34ee64f&msclkid=71f0e79ad2d81d84fe908076c90be9d5&qid=1743526880&sr=8-6&th=1

Mostly I use spray on dry lubes though to avoid attracting dirt, some of them are getting phased out due to Pfas forever chemicals and you need to be careful not inhaling them!

I have some old cans of bostich spray lubes that are for planer beds and table saws, it leaves a slippery coat on the metal but is dry to the touch.

You should be able to see some of the parts wearing already from use and if you get some 600-800 grit emery cloth you can smooth out those areas a bit to accelerate the break in process.
 
Spray parts with G96 and wipe off the excess... Grease on a pump shotgun really is not needed. Excess grease is even worse. Hoppes #9 is a solvent and very runny.

The title is mis leading... Hard ejection after firing sounds like the problem.
To expand on that, when brass expands after firing in an imperfect or out-of-spec chamber, the brass literally fire-forms to the imperfect size or machining/tooling marks in the chamber itself. The "polishing" is meant to smooth that out/make the chamber more slippery...but only if the chamber is the issue.

Seems like a problem that plagued 870 Expresses for a while, never heard of that being an issue with Mossberg (even the 88s) so seems unlikely as the cause on a 590A1. Not impossible for sure.

Question-does the stiffness occur with snap caps or at any point OTHER than after firing a live round? If it's jamming any other time I have my doubts it's the chamber.
 
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To expand on that, when brass expands after firing in an imperfect or out-of-spec chamber, the brass literally fire-forms to the imperfect size or machining/tooling marks in the chamber itself. The "polishing" is meant to smooth that out/make the chamber more slippery...but only if the chamber is the issue.

Seems like a problem that plagued 870 Expresses for a while, never heard of that being an issue with Mossberg (even the 88s) so seems unlikely as the cause on a 590A1. Not impossible for sure.

Question-does the stiffness occur with snap caps or at any point OTHER than after firing a live round? If it's jamming any other time I have my doubts it's the chamber.
It seems like the worst of the problem was on the weekend at the club when firing the slugs. After that, I shot a few more but it was super stiff but it's not consistent - it's on occasion and there's no rhyme or reason.

After lubing, the fore end occasionally is stiff/stuck in cycling through the occasional snap cap - same type of behaviour as the club, but it wasn't stuck as badly - it's like it gets to 10-20% of the racking and then it gets stuck until I then heave on a subsequent pull back, and then the round / hull is ejected. I did put it back together properly as it passed all the function tests.

I will concede while it may be as simple of an explanation that I am not "shucking" it hard enough, I rack the forend back the same way and with the same speed/vigor as I do on my old 590 Shockwave and the same way I do with my 870, and the same way I do with my Supernovas (the Supernovas NEVER had a problem even close to this).

I will disassemble it tonight and clean off all the oil and G96 it and then assemble it back and take it to the club on the weekend to try again.

This was going to be the HD gun had the Liberals banned all SA shotguns - I am glad I am noticing this now rather than in a HD situation...
 
Seems common with the cerakoted ones from reading reviews. Let's say it's not hard to notice a trend
 
It seems like the worst of the problem was on the weekend at the club when firing the slugs. After that, I shot a few more but it was super stiff but it's not consistent - it's on occasion and there's no rhyme or reason.

After lubing, the fore end occasionally is stiff/stuck in cycling through the occasional snap cap - same type of behaviour as the club, but it wasn't stuck as badly - it's like it gets to 10-20% of the racking and then it gets stuck until I then heave on a subsequent pull back, and then the round / hull is ejected. I did put it back together properly as it passed all the function tests.

I will concede while it may be as simple of an explanation that I am not "shucking" it hard enough, I rack the forend back the same way and with the same speed/vigor as I do on my old 590 Shockwave and the same way I do with my 870, and the same way I do with my Supernovas (the Supernovas NEVER had a problem even close to this).

I will disassemble it tonight and clean off all the oil and G96 it and then assemble it back and take it to the club on the weekend to try again.

This was going to be the HD gun had the Liberals banned all SA shotguns - I am glad I am noticing this now rather than in a HD situation...

Sounds like you’re doing your part Gazelle, I can see “stiff” on a new gun but yours sounds barely functional. I’d be watching (maybe more importantly?) that it locks up tight too?

When taking it apart, look at the action bars loose and compare against images online as an option? I’d be wanting to confirm the flatnesss is the same, and look at any points of wear. Haven’t owned a CK’d gun before, but on a well-used 500 the internals fall into place on reassembly. Nothing overly tight. Watch for tight fitting parts, and inspect where the action bars are moving in/out of. Feel for burrs, try to slide them loose and see if they’re hanging up on anything?
 
Sounds like you’re doing your part Gazelle, I can see “stiff” on a new gun but yours sounds barely functional. I’d be watching (maybe more importantly?) that it locks up tight too?

When taking it apart, look at the action bars loose and compare against images online as an option? I’d be wanting to confirm the flatnesss is the same, and look at any points of wear. Haven’t owned a CK’d gun before, but on a well-used 500 the internals fall into place on reassembly. Nothing overly tight. Watch for tight fitting parts, and inspect where the action bars are moving in/out of. Feel for burrs, try to slide them loose and see if they’re hanging up on anything?

There are a couple things I have noticed in following probably the best video on Youtube on taking apart and 590A1 - the camera angles were superb. I don't know if this is consequential or not...



1. The lifter is the first thing that goes back into the gun - it has two little recessed points where it connects to the lifter and acts as a hinge. In the video, the lifter by default pops up unless pushed down (approx 7:48 point). Mine stays down - again, I don't know if it is of any consequence.

2. The part where he has the bolt turned over and says to push down on that square nubby thing on the bolt (around the 8:08 mark), in order to make it slide in easier...mine does not stay down - it pops up. I don't know if there is any consequence or not.
 
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Which model do you have? Is there a rail on top? Any screws protruding down into the receiver for some reason?

Something doesn't seem right that's for sure.
 
Which model do you have? Is there a rail on top? Any screws protruding down into the receiver for some reason?

Something doesn't seem right that's for sure.
No I bought it new retail, no rail on top though it is drilled and tapped.

No screws protruding into receiver.

It is a 590A1 Marinecote, model 50767.

I will see how it is when I take it to the club and may use it for a while and maybe it will get better. BUT just in case...does anyone know who warranties Mossberg in Canada? North Sylva?
 
Right on, maybe they did put the marine coating on a little to thick somewhere.... you should be able to see the wear points.

On a different note, if you like the shiny nickel plated shotgun look, the EGE Arms PA37's have been pretty cheap lately..... :)
The Ithaca 37 action is about as smooth as a pump gets!

EGE_Arms-1__18985.1740579574.jpg
 
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Yes made in Turkey, They seem to have good reviews over the last few years they've been around, the firs ones were Branded Canuck and they were more expensive, The sale price and the fact they are Not stamped Canuck and have more of a minimal branding is more my style!

I just ordered a black one from SFRC yesterday during their quick 10% off free shipping day, could not resist for around $380 shipped and taxed!
I'm a fan of the Ithaca 37 design... :)
 
My 590M was pretty stiff when I first got it
I used super lube grease on the action bars and on other areas that slide and it loosened up after firing a bunch of rounds
The coatings they use on the parts I think are rough/abrasive and just need to wear in some
 
I honestly wonder if I got a lemon here. I remember when I took off the magazine tube cap yesterday, it was VERY stiff. After I reassembled the gun, I couldn't get it back on without tools - used a thick punch to put through the swivel stud and then tightened that way - there was no way I could hand tighten it even to the racheting point. It didn't go on crooked.

Today, when I tried to loosen it, it wouldn't loosen by hand. When I turned the swivel stud with the punch, it just loosened the swivel stud. So I took some locking pliers, wrapped a silicone glove around the cap and then loosened it that way. After reassembling everything again I looked at the cap - it goes down but doesn't seem to catch any of the threads and when it looks like it does, I couldn't hand tighten it, just like yesterday. So I used the silicone glove to wrap it cap, and then used the locking pliers to tighten again. Wasn't a lot of force with the locking pliers,

My 590 Shockwave wasn't like this, and obviously neither were my Supernovas.

I will just resign that I may not have to clean this thing. If for some reason the extremely stiff fore end problem doesn't get better, I may send it in so they can look at the cap threading issue as well.

Sure, I could be a weakling, but none of my other shotguns with magazine tube caps have this issue.
 
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