Okay the Ammo Cartages are the empty clips that falls on the ground when reloading the lancer
Well i can tell you how to make a huge pile of them super easy and only shooting a little bullets
1st: Shoot 3 times or 1 time doesn't matter
2nd: Hit the RB Button and press B
So as soon as you hit the RB Button Tap B and keep doing RB-B-RB-B-RB-B
If you still don't know how to do it add my GamerTag on Xbox and i can Show you
P.S I know its not big or a special glitch but its just 4 fun
Have FUN!
Gamertag: xXSharpK1ll3rXx