I love peep sights. I'm slowly converting all my guns to peeps. FAR MORE ACCURATE.
Here, let me teach you how.
1) Take your Garand, and hold it at the ready.
2) Look ABOVE the rear sights, and focus your eyes on the front sight. Got it? Good.
3) Now, without taking your eyes off your front sight (which is perfectly focused), move your face around, until your eyes are still perfectly focused on the front sight, but now, you are seeing it through the rear sight.
4) Don't look at the rear sight, the rear sight should be a fuzzy gray ring. The Parallax curvature of objects when viewed as a close byline of another object (Sometimes referred to as the "Einstein Effect" because light is slightly bent at the edges of the rear sight due reflection (or lack thereof), and Einstein, using this theory, said it it worked for light we can see, maybe it works for gravity we can't see, and thus his explaination of gravitational fields as a mass punctuation against the fabric of space.. but I digress)
5) The fuzzy ring will feel uncomfortable, DON'T FOCUS YOUR EYES ON IT. Keep it focused on the front sight. You will move your gun ever so slighly until the fuzzy ring feels "evenly spaced out".
You are not perfectly aimed.
as for Garand Thumb.. I'm left handed... pretend you are left handed, and load a Garand.. you will know what a Garand thumb is :banghead: