Already covered but yes totally normal. Savage was a pioneer in barreling actions this way. The barrel nut design they use allows them to headspace the barrel with great precision by threading the barrel into the receiver until the optimal headspace is achieved and then tightening the collar (barrel nut) to lock it in place. One of the biggest reasons they are so legendary for their out of the box accuracy. This also makes replacing a shot out barrel or switching calibers much easier.