ar15 iron sights

Ok, new to the platform and just built my first gun. I have flip up sights...back has a circle aperture (can choose between big ring or small rint) and front has a half moon with an adjustable middle sight for up and down. Do I line the front sight up with the tip of the sight on the target, or the middle of the post on the target?

I know its a noob question, but I dont know. With bb and pelet guns, the front post takes up the whole slot in the back sight, but when looking through my ar sights...I see the whole front sight through the back hole.

any and all help with be greatly appreciated.

thanks

Short video that should help

AR 15 Sight Alignment

Longer but better

Service rifle - Sight Alignment

Good videos.

very simply put! Thanks and good videos.