I completely agree with you and I honestly believe that 99.9% of the time it would load and function properly. I have a buddy in the Army that is an armorer and he and I had this debate, now granted he is indoctrinated and firmly believes the rifle will fail if loaded in this manner. According to him, and this is what i am basing my info on with a little bit of extra reading as well, in a firearm that is designed to be loaded from a magazine, it should be chambered from the magazine to ensure proper seating of the bolt and to make sure it will eject correctly. He said that Glocks have had failures when breach loaded vs. magazine loaded.
Definitely don't want to argue about this anymore because it isn't that important to me. But in a hunting scenario when you already have a loaded magazine i would think it would be easier to just insert the mag and charge the weapon vs. hand loading and then inserting a mag.
