RE: Sighting in G5 Optix sight - Please help
In response to your 1st question: An arrow travels in anarc or parabolaand as a result crosses your sight plane in 2 places when you shoot. Same principal as a rifle. Therefore, if you had a pin sighted in for 50 yds it would also be on at 4 to 5 yds.This is why if you shoot your 20 yd pin at 10 yds it will typically shootlow and why people say that under 10 yds to not use your 20 yd pin or you will be very low.
For the second question the 275 will get you close. If you wanted to you could use the 275 before even going to the range and then adjust the housing vertically. Just make sure the 50 yd pin is the whole way up or you will be sighting in all of them again.
Hope this helped you out and enjoy shooting. The ME is a great sight.