How much time are you leaving between the end of the ceremony and the start of the cocktail hour?
My non-Mass ceremony will be at 5, so "the gap" is not an issue for me. I just want to time it so that guests will get to the cocktail hour and have enough time to enjoy the drinks, hors d'ouevres and brass trio we're providing, but I also don't want them to be waiting around to get in. It's a 10-15 minute drive btwn. the church and the reception. So, I was thinking:
5:00-5:30 Ceremony
5:30-6:00 Receiving line (is this too long? we will prob end up around 200 guests)
6:00-6:15 Travel time
6:15-7:15 Cocktails