Can't open PET bottles

[LeftyRighty]

Am re-using PET soda bottles. Thoroughly rinsed and dipped in StarSan, then racked until filled with beer. Problem encountered is that the caps require excessive force to open, even having to use pliers a couple of times.

What's with this? Is it carbonation pressure (doesn't seem higher than soda) or does the StarSan seal them? I know that the StarSan is not completely dried yet in the grooves/threads of the bottle and cap. Any suggestions?

 

[estricklin]

Gently tap the caps in a horizontal motion with the handle of a screwdriver or something before trying to open. See if that helps.