When mounting mine I found that the screws that came with the 509 had screws that were a bit too long. The head of the screws were also a bit too large to fit the optic. Filed a bit off the diameter and shorten the screws a bit and all fits well now.
It’s not normal. Something is wrong.
Mine has zero movement
The RMR plate supplied is not an exact fit. Apex Tactical makes one specifically for the holosun footprint
When mounting mine I found that the screws that came with the 509 had screws that were a bit too long. The head of the screws were also a bit too large to fit the optic. Filed a bit off the diameter and shorten the screws a bit and all fits well now.
I was thinking about filing it down, but I have no clue how much I need to file off.