The shell_table.lua has these values. This means the dispersion is dependent on the ammunition, and not the gun itself or the rig. What this leads to is every plane using the M61 will have these spread patterns.
I looked around the forum and the issue seems to be for the F15, too.
I have read a report on how these clamps have not been used in combat, so shouldn't the Hornet get the stock clamp, that is widely used?