How long is the despawn timer on dropped items?

[Xelacalle 0]

So I've been playing this game for a couple of weeks now, and I've managed to get two of my friends to join me. We've met up, got ourselves hunting knives, hatchets, matches, and a water bottle. Next we plan to raid one of the smaller towns we're nearby.

One of my friends is currently using a crossbow with no bolts. Obviously, it's pretty useless and my friend would much rather have his hatchet out while he goes through the town, so the plan is to leave it with me on a hillside as I watch out for other survivors and watch the zombies with my hunting rifle's scope.

As none of us have the space to keep the crossbow in our packs, my question is this: How long can I leave the crossbow beside me before it will despawn? Can I pick it up and put it back down again to reset the timer? And finally, am I in any danger of losing my hunting rifle in this situation? (I've had weapons disappear while dropping them before.)

Thank you in advance for the help :)