Use 5 hog panels in a circle around your feeder to keep the hogs out .This gives the deer plenty of room and doesn't
concern them . Drive a T post at each connecting point and your ready . If you want hogs and deer put your feeder close to the perimeter so some feed goes out of the ring . If you want only deer put it in the middle so feed doesn't go out of the ring . This has worked great for my hunters . This also
protects the leesors cattle from bloat should they knock the feeder over and eat to much corn . I have lost cattle that way.
Do you have any other ideas .

Use cattle panels, because cattle can and will occasionally, jump hog panels. I build square pens with 8 cattle panels (minimum) and 16 t-posts because the cows will push on the panels.

Either way will work, but square is easier and faster for me.

Round pens work best. Mature bucks will get a small buck in the corner and gore them to death. Unfortunately I have seen it happen. The round pen gives the young bucks a way to get a way. No corner. Just my 2 cents.

We do a square with 8 panels. I would say 5 may be too small.

If you can afford it and have space, I like the idea of making them as large as possible. If you hunt on a ranch that has cows or sheep, a large pen can allow you to plant a small food plot w/o having to worry about other animals grazing in it.

Whatever works for you... We use the 16' long, 34" high hog panels, four of them, in a square, barbed wire around the top and middle. Never had one deer gore another, hogs and cattle stay out, some corn stays in, some goes on the outside. Deer jump in and out without thinking about it. No probs..