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Mossberg 590 Pump Action Troubleshooting

FS woes:

Just received a brand new 18.5" barrel ffor the 590A1.

I had it sent directly from Mossberg to Vang Comp.
VC gave it their treatment and sent it to me.

Got it on the gun and the front sight seems noticeably canted to the left.

Any prior experiences with the issue?
Anyone know if VC indexes their ports off of the FS?
They seem symmetrical to the FsBase. So I'm concerned if I have to have the FsBase moved its going to throw off the port work.
It's too early here (East Coast) to reach VC or Mossy so I'm hoping to get some help here first but I'll reach out to them and post up news here as soon as I get it.
 
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Ok all, quick update;
Spoke to Xody at VC. Great guy great CS at VC.
I was hoping that VC may have checked the trueness of the FS before beginning work. VC does not have a receiver jig thy they work off of so they rely on Mossberg's work to determine where the pots are going ie they DO index their ports off of the front sight base. (Completely logical and understandable so no "knock" there I'm just filling everyone in)
2 Cosy felt moss ergs sometimes come in canted but it is not that often. It's a more rare thing than on other shotgun brands they work on and they require those brands to send in the receiver weigh the gun.
3 I shot the heck out of that gun yesterday. The VC system kept all shots from OO inside the 8 of a B40 at 25 yards and probably would've done better if the shooter was a better shooter. After doing some tinkering we concluded the dovetail sight blade was canted and crooked as heck but the base itself was fine so I'll be contacting Mossy for a replacement Monday.

Thanks all for listening. Lmknif you have any questions.

Ed. to add;

A Choate type mag ext was used. It got me a true 2 rounds with buck, slug and bird. It ran fine when directly attached to the mag tube. However, I ran a wilderness products front sling plate between the tube and the ext.
BE WARNED: the gap created by the sling plate between the mag tube and the extension causing the spring to hang up on the mag tube lip and jam the hell out of the mag tube spring. Feeding was totally dependent on gravity and tilting the gun up after each ejection to feed a round out of the tube. Pulling the plate and re-attaching the ext directly to the tube cured this for the rest of the day and well over 100 rounds of mixed lot with no hiccups.
 
I have a few questions/concerns about my new 590a1 8 shot.

1. There is noticable lateral barrel play where the barrel meets the receiver. If I grab the barrel ring and rock it side to side I can notice the play.
2. I have a very slight amount of play in the trigger housing.
3. My safety is very hard to manipulate to the fire setting. So hard I actually need to use a towel between my thump and the safety when pushing it because it tore my thumb to bits.

Are any of these major concerns?
 
I have a few questions/concerns about my new 590a1 8 shot.

1. There is noticable lateral barrel play where the barrel meets the receiver. If I grab the barrel ring and rock it side to side I can notice the play.
2. I have a very slight amount of play in the trigger housing.
3. My safety is very hard to manipulate to the fire setting. So hard I actually need to use a towel between my thump and the safety when pushing it because it tore my thumb to bits.

Are any of these major concerns?

My safety was really hard to manipulate in the beginning as well. After a while it was ok though. Play with it a little bit and it will loosen up... a little bit of lube will also help.
For the other problems now... the thing with the barrel sounds a little serious and I believe you might consider taking it back to the place you bought it and show them what you have noticed... and since you are there show them the play in the trigger housing too :).
I hoped I helped you my friend!
 
Can you follow through with the shot by holding down the trigger and racking the action? When I do this and let off the trigger the hammer goes off. Maybe you're not supposed the hold on the trigger while racking the shotgun but still it does not feel like it's supposed to be doing this. It feels like the disconnect slipping off of the Sear. Am I right... anyone with knowledge of this?
 
Can't say why it's doing that but no, it's not supposed to work that way.
 
OK Fellas today me and the wife went out and did some shooting, we took the Mossberg 590A1 "US Service Model" and some Winchester-mart low-brass #8 bird-shot, and after 4 shots the action locked up and it took some hard jiggling to get it to cycle the next round in. After a few more shots the action seemed to get real stiff. Now we only fired 9 shots and turned to the handgun for some shooting with it. This shotgun cooled down from what little it heated up and it seemed to cycle fine or loosely. After every outing I clean and lube my guns no matter what we shot or how much we shoot. I tell you it felt dry to me like maybe I forgot to lube it up proper, now you guys may find this hard to believe but I have made mistakes before, I know, I know, it is hard to believe but if I'm an honest man I must tell the truth. All that being said, Any Help or comments is much appreciated.
 
I don't worry much about cleaning and oiling. I can't remember when I last cleaned my guns with anything more than a bore snake and I only very lightly oil when I have them broke down. My 1911 is another story.

After the outing (or during) how much investigation did you do to identify what may be happening? For example, before taking it apart for cleaning, did you check how the action bars were interacting with the cartridge stop? That's what I would suspect first.

It's difficult to get a Mossberg so fouled up and dirty but if you're using a grease rather than a light oil, I suppose it may be possible to get the action sticky enough but that would seem to be low on the list.

I'm curious now and only guessing.
 
OK Fellas today me and the wife went out and did some shooting, we took the Mossberg 590A1 "US Service Model" and some Winchester-mart low-brass #8 bird-shot, and after 4 shots the action locked up and it took some hard jiggling to get it to cycle the next round in. After a few more shots the action seemed to get real stiff. Now we only fired 9 shots and turned to the handgun for some shooting with it. This shotgun cooled down from what little it heated up and it seemed to cycle fine or loosely. After every outing I clean and lube my guns no matter what we shot or how much we shoot. I tell you it felt dry to me like maybe I forgot to lube it up proper, now you guys may find this hard to believe but I have made mistakes before, I know, I know, it is hard to believe but if I'm an honest man I must tell the truth. All that being said, Any Help or comments is much appreciated.
How many rounds total have you put through that shot gun?
 
Matthew Malay, I have maybe, maybe, 500 rounds through it. did I say maybe?
Rossignol I have not broke it down yet I just got home. Yesterday I only had to jiggle it some to get it to eject the stuck fired round and then cycle the 5 rounds left in the magazine tube but it seemed to me the cycling afterwords was sluggish so I stopped firing it and just shot my sidearm. I am going out back to put a few more round through it to see if it is still acting up. It is funny you mentioned grease, because I believe I did use grease the last time shooting it. It sat in a scabbard next to the bed loaded with two rounds of #4 Buck 5 rounds of 00 Buck and 2 rounds with slugs.
I Shall Return.
 
NOTE- I posted my last post yesterday but for what ever reason I had to re-post it today.

Anyway, I broke down the 590 yesterday after firing more rounds, 10 #8 Bird shot and 10 00 Buck Shot no problems. So I used a youtube video just to make sure I did not miss anything. What did I find? Nothing, so I cleaned and oiled as instructed then reassembled. Racking it, it still seems tight, but it is still relatively new as far as shooting it goes. Like I said she still only has about 500 round run through her. I have had it a few years it is as mentioned a 590A1 "US Service Model", that sat in the scabbard next to the bed and didn't get much attention after receiving my 930 JM Pro.
Next move I will buy 200 rounds of the winchester-mart #8 and shoot away.
 
I had wondered if it's the shells but Winchester anything shouldn't be a problem. If it isn't gummed up grease, the next thing I'd suspect would be interference between the action bars and cartridge stop.
 
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