As the title says, it only happens with .223 remington. I never had this problem with .308, 30-06, .30-30 or 7.62x39. When the powder bar assemly moves about a half way back from right to the left, slotted bellcrank assembly, powder bar assembly and the failsafe rod are not operating smoothly. At that point, the powder bar assembly stops for a split of a second, before it goes back to the left, and my 550b automatic powder system turns into a salt shaker. It happens on every 3rd or 4th round, regardless of the powder I use (Varget, Benchmark, IMR 4064, IMR 4198, H-335, RE-15). I called Dillon several times. Everyone I talked to was very friendly. Several things were suggested: adjusting the failsafe rod and cleaning the powder bar assembly. However this thinkering did not solve my problem. I called again this morning, and was told that "some powder leak is normal with .223 cases because of the small size of the case mouth" 550b owners, have you run into this problem when reloading .223? Any help is very much appreciated.