Marlin 42 pump shotgun

[A.J.R.]

I recently purchased a Marlin 42 pump in good condition. I have cycled the action with snap caps and it seems to be functional, however after firing the action remains locked and cannot be opened using the pump. In order to eject the snap cap I have to release the action using the button near the trigger guard. Is this normal? Thank you.

[Regnier (gunrunner)]

A.J.R.;

Yes, this is how it is supposed to function. The "button" you refer to is part of the safety system Marlin developed called a "Hang Fire Safety" and the release is the "button" down by the trigger guard. When the gun is fired, the recoil "sets off" the hang fire safety system and the action will open without having to use the "button". Since you are using Snap Caps, there is no recoil, so the system is not "set off" to release the action.
Earlier Marlin shotguns had the safety release up near the hammer and really was easier to use. Marlin changed the system on later guns and the "button" you have is part of the hook that holds the breech bolt locking bolt and prevents the breech bolt from opening.

[A.J.R.]

Thank you very much!