Not weak, IMO, but not the bastions of strength that a good bolt gun is either. They are a little "stretchy" but no worries thereof as long as the user isn't an idiot and tries to make his .300 Savage perform like a .300 magnum. Any rear locking lever gun bolt is going to move more than a front locking bolt.
99's were chambered in some righteously high pressure cartridges- .22-250, .284, .308, .358. I never ever heard of one coming unglued.
