I just finished my first build. Mega Lower and 20" A2 from M&A sales. Rifle looks great and shoots great. However I have one question. When I shoot Silver Bear ammo(zinc coated steel) it piles the emptys about 5-8 feet to the right and rear, just where my Bushmaster does with all emptys. However when it spits out Brass cases it sends them forward and right. Not that this is a problem but is this normal? The angle forward is about the same as the angle rearward and distance is about the same. It just seams strange to me it would go from one direction to another. I even had a mixed mag and as soon as the brass cases came up it started spitting them forward just like when the mag is loaded with all brass.

That's the undocumented brass sorting function!
At least, that's my best shot at it!  My BM does the same thing.  I just assumed it was the different weight, ot hardness between the steel and brass cases.

If the brass is ejected hard off the deflector, the brass goes forward.  Shoot the brass cases and watch the deflector for the brass bouncing off.

I've never shot anything but brass cased ammo and I've found various landing positions for it as well. I think it has more to do with how hot the load is.

Different weight of cases and function of pressure and duration at gas port affecting speed of the carrier.  ARs have nice soft ejection and with nice consistent ammo will almost or will throw them all into a 5 gallon bucket.  Of course, carrier speed is slowed by magazine friction too, but it is by far the most consistent ejecting gun ever.

now that is a idea, i want to try that