Originally Posted by Gbannan
Understood. I'm assuming operate the slide and check to see how smooth it operates. Excuse my ignorance.
Generally it's more of an issue of appearance. The gas block would have to be canted pretty severely to hinder the movement of the gas piston. Though operating the action doesn't hurt any.
The time when a canted gas block can be an issue is if you are mounting a handguard where the upper and lower clamp together, or when using an Ultimak.