There are plenty of boats built in the 70's that would suffice for ocean travel and as mentioned, certainly the Cal 40 is one of them. But, if you truly are going to sail offshore, then you want a boat with that A "ocean" classification as mentioned above. That means the boat is designed for extended voyages where wave lengths of 4m and more can be realized and force 8 Beaufort scale conditions can exist. To accomplish this, the boat is built to better specifications with better hull to deck joints, more substantial windows and hatches, cockpits that are safer with higher bridge decks, robust companionway doors, larger scuppers, etc. Engines are more than adequate for extreme conditions and fuel tanks are larger so you can motor greater distances when the wind isn't blowing. Your water supply is larger as well. Interiors are designed for live-aboard use where you have places to stow needed items that don't collect in the living areas of the boat. Hull and deck construction is well done, with safety in mind such as having stanchions that support lifelines that can withstand the abuse of someone crashing into them. Proper hand holds inside and out so you can make your way around the deck and inside in heavy seaways. The rig and standing rigging are adequate for offshore use as well as the sails and sail handling equipment. Winches and other deck hardware are adequate and you have enough for all the tasks at hand. Many production boats keep the price down with smaller engines, fewer winches to do more things, sometimes even one pump to accomplish many tasks selected by shutting valves and opening others. I have written lots on this before, but people don't like to search old posts. They just keep asking away. Lots of people have contributed lot of good (and bad) information in this forum site. Safety gear is another thing you need to consider for offshore use. Someone mentioned Merlin. Well, that boat was designed for down wind racing, which is what the Trans Pac is all about. The original mast off of Merlin actually ended up in my boat yard and I retro'd it for an Eva Holman 52 (or was it 53?). Then electronics for navigation is to be considered. All of this stuff is based on your budget, but also you have to prepare yourself for such voyaging and passage making. You can get your ass kicked on the open ocean. Not for the feint of heart. If it is coastal cruising you think you will do, then classification A or B and even C works depending on the conditions you will sail in. Coastal cruising usually means, for the most part, but not always, that you can duck in somewhere if things turn bad. Of course watching your weather window is germane, but if you are long off shore, that can change in a heartbeat. So, this is just a beginning - stuff to think about. Somebody also mentioned crossing the ocean in an O'Day 27. Sure it can be done, but not the boat of my choice. My late friend, Gerry Speiss sailed a 10' plywood boat he built across the ocean too. But, he almost went nuts doing it and I like a bit more comfort. I've done some extreme sailing on an Express 27 (which is a very well built boat) and survived (actually had a blast), but I've also done offshore stuff on a 47' ketch (just to name a few). The larger boat was really comfy and fishing off of the back deck behind the mizzen (it was a center cockpit) made for a great place to skin and clean fish without getting all the nasty stuff in the cockpit or living area of the boat. It's all in what you want to do and how comfortable and safe you wish to be. Follow your bliss while you are young and still can do it, but be sensible about it.
