In ref to the 88 round FTF, I am new to AR's. I am an experienced shooter, but having an AR has been a long dream. After reading as much as I could about lubrication and general operation of the rifle, I probably erred by purposly over lubing with Break Free for the first outing. I did the same on my first build, which is a Century M16A2 kit (modified to AR) on a DPMS lower. Did the same thing in over lubbing for the first outing, and had some FTF's. The first build now has about 500 rounds through it, and it functions so well and is so smooth, I used it in a 3 gun march in May (It placed me 10th out of 54 iron sight shooters and 24th out of 98 total shooters).
I did the same early new build over lub on my L1A1's, and got the same type of failures after the rifle warmed up and got dirty.But, after cleaning, they have all been totally reliable and function perfectly. I used the Break Free heavily, knowing that if something would happen, it would on the first outing. As a result, the M&A is 90% smoother in its operation than it was before the shooting exercise. I am certain that one or 2 more FTF's will occure, but I consider (rightly or wrongly) that to be part of the break in peroid. All I need to do is do more bench shooting with it, and I know it will be ready for the next match in October.
BTW, the FTF result was a round with heavy bend marks in the case side from the extension, and the round chambered and stuck, but not in battery. A cleaning rod tap freed the round easily from the chamber. I guess I could have hit the bolt assist and jammed the round in, but, I didn't want to push it. We did do some quick double taps, so I am certain we have everything squared away. Just more shooting!
Also, we were using USGI used mags, so I would not fault the rifle at all. The mags are suspect, but I use the SA80 mags for competition, and they are perfect.