A peep sight is a different type of Iron Sight utilizing the front post (like normal) and a rear circular sight. By looking through the rear circle, the shooter automatically is aligning the sight, and only has to concentrate on place the front post on target. They are generally thought of as easier to shoot than Buckhorn Sights.
The Scout Rifle lists having a receiver mounted peep sight as one of its necessary attributes, to backup the Telescopic Sight in case of breakage.
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