I've done a lot of research on this and have tried just about everything under the sun on the rams on my presses. The best of the current crop of lubricants for the ram is Rem Oil. It's very thin, sort of like sewing machine oil, and makes the ram slide very easily and smoothly. It has Teflon in suspension, which helps the ram movement. Just clean the ram really well before applying and you'll see the difference.
Of all the rust preventatives that I've tried, and it's a lot, the best I've found for guns and reloading equipment is Bullfrog Rusthunter. It has VCI technology, and dries to a clear finish. It really works well, and since I started using it, nothing has rusted. It comes in a spray can and has a really sweet smell.
I live on the Oregon Coast, where we've been known to "occasionally" get a little precipitation and a little humidity. I've tried everything. My tests consisted of a strip of bare metal, divided into squares, with each rust preventative spread into it's square, and left outside for two months during the winter. This is a pretty severe test. I don't live on the beach, but I do overlook the ocean from 2 miles away.
The very best was Rust Guard-It, but it leaves a heavy wax film that stays sticky. The second best was Bullfrog. WD-40 rusted just as fast as the bare metal. Some of the others, such as Break Free and Eezox, lasted just barely longer than WD-40, which surprised me, but like I said, the test was severe.
You can do your own tests with the products available, but these are the results I obtained in my tests.
Hope this helps.
Fred