There are many good calibers for deer. I do believe highly in bullet placement or leave them walk. Almost every year we will let a few bucks walk because of placement. Myself and the people I hunt with it drops right on the spot 99.9% of the time. The other .1% does not go very far, but it can and does happen. The biggest mistake I see hunters make, and even the ones that been doing it for years, is find a little blood and start pushing the deer, till the blood stops. We always of course take a look if you do not see it go down, and look around a bit then thats it. Time wise it depends what time of day it is. Two hours is a good time two wait seems like forever, but most the time within that 100 yard area you will find that deer dead. If you dont after looking real good, and I do mean looking hard, your probably not going to fine it.