If anyone is having a problem with the AMD's not feeding you might try grinding down the selector stop. I had a problem with several of my builds until I noticed that the selector stop seemed rather thick not allowing the mag to seat to the proper depth. Yes, I checked rails and every other thing I could think of and still no luck. This also occured with several makes of mags. I ground down the stop to aboout 1/2 its thickness and that solved the problem. Hope this saves some hours & headaches!! :headspin: