AR rear sight aperture removal?

[berg]

Is there a trick to this? I need to replace the dual aperture A2 flip sight. It looks like there's a pin through the windage knob that needs to be knocked out but I've tried to punch it and it's not budging. I'm working on a removable carry handle with A2 NM rear sight.

[bornproud]

Go get some kind of penatraiting oil (like wintergreen) and let it soak for awhile. Then you should be able to punch it out.

[berg]

Hey thanks, the oil worked!