I noticed that you can look down the barrel of the magnum but not the glock.
Dont know if this should be possible or not. Not a big deal anyway. Just wanted you to know just in case it is a bug.
No, it’s made on purpouse: the issue of the Magnun iron sights was raised after the pre-release leaked video of last month, when people questioned about this feature. One of the developer, Raminator, said the Magmun and the crossbow were the only weapons capable of this.
Short answer: it’s not a glitch, it’s voluntary. 