I have a couple of ten rnd mags for my AR. One extends out of mag well less than an inch and others are flush . I accually like the one that extends ....it is easier to see if it is loaded ,doesn't interfere with shooting from bench or carrying , and gives you something to "hit" to make sure the mag seats all the way up into proper location in mag well.....Mine is a .204 and I have my bullets at 2.262 in length and no feeding problems with a very small bit of room to spare. SM