I purchased a DPMS DCM upper from Midway quite some time ago, and have not shot it at anything but 100yds until recently. It's supposed to have 1/2 minute rear sights in elevation and 1/4 windage, but the clicks that I have to put on it for elevation EXACTALLY match what I put on my BM 1/4 elevation upper. In fact, my 200/300/500/600yd settings are the same. I checked this with a buddy that shoots 1/2 ele 1/2 wind sights, and his clicks are only 1/2 mine, as expected. Was there a change made somewhere to make your DCM rifles 1/4W 1/4E and you just forgot to update your catalogs?
Oh, and it shoots MOA all day long, even in a 20 knot wind.