Case tipping and miss-feeding have been noted with universal case feeders when feeding 223/5.56.
We have come up with a easy modification to improve the reliability when loading bottle neck cases such as 223/5.56.
A notch can be cut on the small orifice of the feed plate as depicted. The notch is 5/16"(.3125) wide and 3/16"(.1875) of an inch deep. A burr in an electric moto tool or a utility knife can be used to cut the slot.
Adjust case feed attach plate so case mouth is a pennies thickness from bottom of slot as depicted.