Like I said prior for myself a .243 would be the min. Lets face it about everything has been taken with the .22lr, but do you really want to use that on a deer. Not me. Has said prior by many shot placement is key, or you leave them walk. That holds for whatever you are using caliber wise. I seen deer wounded with very big caliber rifles, and deer dropped with the small ones. There are way to many people that do not practice enough with what they are using. Take a few shots make sure it is on, and thats about it. You need the practice to be good, and that in turn makes you confident on your own skills. Has someone said bullet make is very important for what it is being used for. I reload, and my wife use's a .243. I would rather her be very good with that, then being worried about recoil from my 06. But that is the smallest I would go for deer with the correct bullet and load. I use a 100 grain Nosler Partition in hers, but there are a few other good ones out there. It holds together great, and expands just right. Last year her first year she shot at two, and got two. One buck double lung shot went about 30 yards, and fell her doe tag with a neck shot dropped right there. Before season mainly during the winter I load us up about 150 or so each. A month before season we go out about once a week shooting at differnt yards, and styles. Bench and free arm both. It is just fun to do, and you get very good. Of course I keep the riflles up on the cleaning. I am not saying everyone needs to shoot that much but alittle bit can go along ways. She knows her placement, and had let many walk because she new it was not a good shot to take. She can shoot my 06, but is much better with the .243 being not worried about the recoil. This is just me, and my thoughts on the matter. I hope you all get a nice big buck!