What I carry is a little different than most of the above. Mostly I hunt in bush with some trails in the foothills. I don't really pack for half a day. I might not know it is a half day until I am back. We just had a baby, so I didn't get out this year, so this is from memory.
* Coat warm hat and Mitts that I am fine sitting in, or spending the night
* map folded to the local area only in a ziplock with a write anywhere pen that works on the ziplock.
- marked with base camp, known trails, roads, clearings, areas of cell reception, and local STARS pickup areas if close enough to the city.
* compass
* gps
*calls
- map compass calls and gps are on the front of me.
* paper towel -- it works when sh1ting like a bear as we won't be flushing, and doesn't dissolve too fast when wet, so it works as a biodegradable path marker. Ever go back to get your surveyor's tape?
* game cleaning gear; knife, saw, tags, enough paracord to pack, or pull a deer out, etc
* headlamp with red filter.
* one extra set of batteries that work in both gps and headlamp
* food and stove
* water in camelback, or canteen. I take about 1.5L, but refill as needed.
* a couple baby wipes.
* sometimes some burlap to make a blind depending on where I am going.
* fire: bic,windproof matches, dryerlint/wax kindling.
* extra set of glasses
* T3 and advil
* a weird 6oz steel bottle that I am not sure what it is for.
* book
* gun with compass, bic and knife in buttstock.
* sometimes rattlebag, rangefinder and pillow seat depending on where I am going.
*large orange garbage bag.
I am probably forgetting a few things, but that comes to mind.
Most of this is in a backpack that is packed so that I know I can be quiet in the bush with it on. About late August of each year, I start wearing it on some of my trail runs to make sure it fits well, and doesn't make noise.