If no one's said all of these yet (and in addition to more obvious practical needs, such as gun, ammo, etc):
- Insect repellent (my last trip was really annoying because of aggressive bugs, and I was foolishly wearing knee-length shorts and sandals, no socks).
- Sunscreen
- Sunglasses / hat (it's sounding like I live in Arizona, but I don't -- summer can be hot anywhere in N. America)
- Extra foam earplugs as giveaways -- I find too many people at the range (esp. girlfriends and wives) with NO hearing protection, and I therefore don't like to shoot nearby, because I don't want to harm their ears. Fingers pressed firmly in earholes and grimacing is not quite the same
- One I've been meaning to add: a deck of cards -- perhaps the world's handiest 50-pack (now, with 4 bonus cards!) of fun, challenging targets. For some reason, it's always fun to shoot at cards, esp. if you get them cheap from a dollar store etc.
- a book, to prevent Dr. Murphy from providing an opportunity in which to read a book.
- notebook; I'm not terribly consistent about it, but I like to at least note approx. how many rounds fired of what caliber, any special notes about the day's session. As someone with a bad head for names, it's a good memory aid when I meet someone new at the range, too.
[EDIT: A few more things I meant to have on this list ...]
- plastic container for gathering brass (my own, and any that gets volunteered to me)
- ruler (for measuring groups, etc.)
- pens / markers (always missing when I want 'em)
- clamps, tape, thumbtacks, other things-with-which-to-attach-other-things; if you shoot at a sporadically maintained outdoor range, having more than one means to attach targets is helpful. One of the many uses of duct tape, too.
- Re: joplinsks's good point above about a soft mat for guns, note that mousepads are excellent for this -- soft neoprene generally, with a non-slep bottom. The mats at the indoor range where I shoot in Philadelphia sure feel like mousepads, even though they are advertising gun companies and are a bit larger.
timothy