On a 3 pin what do you sight them in for? 10, 20, 30? 20, 30, 40? I have only been shooting for a month now and am curious the best distances for the pins. Thanks for the help. Other then practice, this is for hunting.

Most guys with three pins do them at 20, 30, 40.. or you can go 25, 35, 45.. A lot depends on how fast your bow is. Set it up a few different ways, and see what works best for you. When you get your bow set up, get back 5 yards away and see what pin hits the mark. It will surprise you. I use my third pin at five yards, but I use five pins.

im pretty new to archery so i have been shooting at twenty yards a lot. only now have i set up a 40 yard pin. its 0.7 cm below the 20 yard one so not much room for a 30. so my next one will probably be 60/70 or so. when i finally get good enough

20, 40, 50

Most common is 20-30-40. There is absolutely no reason to have a 10 yard pin on any bow these days. Bows are fast enough that the POI difference between 10 and 20 yards is only about 1".