About the speed of spectral light (luminous)

Hey guys, according to the data from maplearchive, the delay of spectral light is 180ms, which should be about 5-6 hits per second. However, I recorded a video of using spectral light at 30 fps and watch it frame by frame. I found that it actually has 8 hits per second (under dark mode, not necessarily account for sunfire buff), which should be about 120-130ms per hit. Any ideas about this?