Overflow tank bubble/gurgle as you remove rad cap. Concern??

[Pathofinder]

Ive noticed the 3 times I removed the radiator cap that the overflow tank bubbles and gurgles as you twist it off and start to lift it. Is this normal??

Even after replacing it with a new Prestone rad cap from Oreilys it still did this.

Could it mean anything is wrong? I cant tell if its pushing coolant from the rad to the overflow or whats going on, but it sounds like your blowing bubbles in the overflow for 2-3 seconds

[fueler]

i wouldn't worry about it.

[Densetsu]

As long as your coolant levels stay the same, and you don't notice any sudden spikes in your temp gauge, it's OK.