In General,Google cal has no auto synchronization feature.
But you can do it by a little change in iCal link:
To auto synchronize your iCal Feed with your Google calendar change the “webcal” part to “https”.
Example:
Link of iCal Feed:
“webcal://ical.detailsdetails.eu/artist/…”
Link to be Pasted in Google Calendar:
“https://ical.detailsdetails.eu/artist/…”
This will enable your iCal Feed to auto sync with Google calendar.