I know that the head space is set with the bolt face on a #1 MK3 SMLE but should the barrel be screwed in tight? I have one with matching serial #'s so the barrel, bolt, and receiver are meant for each other but if I tighted that barrel all the way the sights are on the side and the notch for the extractor wont line up with the extractor. With the bolt closed and a round in the chamber the barrel does not move. Is this normal?