There's a lot of good advice already, so I'll just add a few thoughts.
As everyone said, you want to use LMR-400. However, depending on how you route the cable, you may want to consider LMR-400 UltraFlex. It uses a stranded center that makes it more flexible with similar operating characteristics to LMR-400.
You'll also want conductive anti-seize on the connections especially if you are going to be connecting / disconnecting them often. I like Jet-Lube SS-30; I use it on all my connectors. A little goes a long way.