Where does this Mossberg 500 gasket/o ring go?

[yow]

I recently got a (new to me) Mossberg 500 from EE, and while I was handling it and cycling the action I noticed this small rubber gasket/o ring thing on the floor. Is this from somewhere on the gun? If so, does anyone know where it goes?

Thanks!

 

[Lodi]

It goes on the dowel that is used for the magazine plug, there is usually one on each end about an inch from the ends. They are to help prevent the plug from falling out.

 

[struff55]

Mossberg technology

 

[Suther]

It goes on the dowel that is used for the magazine plug, there is usually one on each end about an inch from the ends. They are to help prevent the plug from falling out.

I feel like they help minimize noise from the plug hitting the spring too? Maybe? Never really tested it, but my semi with a plastic plug rattles a lot...

 

[diananike]

It goes on the dowel that is used for the magazine plug, there is usually one on each end about an inch from the ends. They are to help prevent the plug from falling out.

The wood dowel magazine plug (limits magazine to 2 rounds for bird hunting regulations) has 2 such rubber o rings on it.
Likely one of yours fell off the plug and wound up in the action somehow.

 

[sherlockbonez]

It goes on the dowel that is used for the magazine plug, there is usually one on each end about an inch from the ends. They are to help prevent the plug from falling out.

Lol but they are not able to prevent themselves from falling out. Engineering at its finest.