ejection cover

[artmcl]

new owner new to ar's just bought new m&p15 ll ejection cover
stays open and does not close. please help

Art

 

[tcon]

The cover should have a spring-loaded ball bearing on the middle edge. Does it depress? The cover is manually closed. Press this area firmly at the top and it should seat closed and make a snap. It automatically opens when the bolt slides back either by discharging the firearm or manual cycling of the bolt.

 

[artmcl]

ejection port

sorry for dumb question thanks for answer

 

[Kadonny]

The dust cover is meant to keep dust/debris out of the rifle when not shooting. While shooting it remains open to allow the ejection of the cartridges.