Pump is stuck on Mossberg 590. What can be causing this?

[WrongHanded]

At a guess, I'd say the ramp is jammed up somehow. Which in turn is stopping the bolt moving either forward or backward because the two are linked.

 

[skeeterfogger]

S

If you buy a firearm at some stores it is locked such that the bolt cannot be opened until the locking device is removed after you leave the store. In any case the criticism during the purchase doesn't serve to help answer and/or solve the original question. Be kind and be helpful! You will live a more harmonious life!

Such things are only as applicable.

 

[kBob]

I am wondering if someone at the gun shop may have tried to learn how a factory new Mossberg 500 series works, broke it down with their native intellect rather than instructions, and just brute forced and ignoranced the thing back together. As noted it looks like the elevator studs are not fully engaged so the bolt carrier might be squeezed between that fork and jammed. Also it may be that someone managed to get it back together with one or both shell stops loose (they are annoying when reassembling) and then bent one or both working the action, wedging everything in place.

Honestly I would try to remove the barrel and magazine and parts and then remove the trigger mech and look in from the bottom.

I do not know what sort of store you bought the gun from but if they are not cheerfully helping I would try to shop for everything some where else.

-kBob