^ This. Is that first handloaded round not chambering at all or is it not ejecting after firing?
Begin with the rifle bolt down on an empty chamber and no magazine in place. Load the full magazine into the magwell and hit it on the bottom to lock it in place. Then rack the bold back and release. Does it chamber the round, or is it failing to strip it from the magazine? If it strips it from the magazine, does it chamber, or is the bolt only partially closed?
Or, if it closes, locks and can be fired, then what happens when it tries to extract the case? Is the case sticking in the chamber, or is it pulled from the chamber but not being ejected and hanging up inside the upper receiver as the bolt moves back?
Detail please. And, yes, a photo would be helpful.