Iron sight issues - AR General Discussion - M4CARBINE. net I just purchased a BCM 16" middy from G R I installed my usual sights (DD fixed front and Matech rear) and noticed that I have to use a lot more of the elevation adjustment and slightly more windage than I am used to I have used this sight combo for years and have never had a front sight need to be adjusted this high The rear sight I can live with, but it’s more right of center than any