I just bought a new 590A1 18.5 barrel. I have not put a live round through it yet but I wanted to get the feel of it so I started cycling dummys through it. I have noticed that the last round gets jammed almost every time. The forend sticks in the forward position and the round will not eject and the bolt release is stuck in the compressed position. I can ultimately get it to eject but I have to lean into it heavy. I since replaced the spring, follower, and installed Magpul furniture but the issue still exists. Does anyone have any recommendations for what might be causing this? My Remington 870 has had thousands of rounds pumped through it and never had a single issue. Mossberg is causing problems out of the box.
Mossberg 590A1 cycling issue
- Thread starter Big Jake
- Start date
Bobster
.30-06
Welcome Aboard! 
Is the entire gun new or just the barrel? Some Mossberg shotguns need to be "broken in" with a certain number of rounds before they "loosen up". The owner's manual might outline a procedure. If only a barrel, it might need a little smoothing of the approach to the chamber.
Personally, I like to tinker with guns so I'll take a new (or new to me) gun apart and smooth sharp edges of stampings with a jeweler's file or similar. Do not smooth things like the sear or extractors, etc.--stuff that is supposed to be sharp. I find that "easing in" a gun (as I like to call it) helps me to understand function better and makes the gun potentially smoother right off the bat without breaking it in. If you are comfy disassembling a gun there are plenty of instructions here if you search or videos on gootoob...
Is the entire gun new or just the barrel? Some Mossberg shotguns need to be "broken in" with a certain number of rounds before they "loosen up". The owner's manual might outline a procedure. If only a barrel, it might need a little smoothing of the approach to the chamber.
Personally, I like to tinker with guns so I'll take a new (or new to me) gun apart and smooth sharp edges of stampings with a jeweler's file or similar. Do not smooth things like the sear or extractors, etc.--stuff that is supposed to be sharp. I find that "easing in" a gun (as I like to call it) helps me to understand function better and makes the gun potentially smoother right off the bat without breaking it in. If you are comfy disassembling a gun there are plenty of instructions here if you search or videos on gootoob...
Disclaimer. I’m not advising you on this and in no way am I suggesting this. Load up a full magazine tube plus one of 12 gauge shot shells. With the muzzle pointed in a safe direction (on the range if possible) start to fire the weapon to cycle through all of the shells until empty. See what happens when you get to the last round.
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