Can you give us a little more information about the rifle? There are two versions of the band retaining spring. The original design was a millled spring that fit into the groove between the rear barrel band and the front barrel band and snapped into a hole at the rear of the front bb. the second design was a late war stamped band spring adopted for use in 1943 and then, very late in the war, both bands were held on with wood screws and have a single hole drilled thru them to accomodate the screw. If you are missing the band spring you should attempt to find the one that was originally used on your rifle. On the top of the receiver you will find the manufacturer's code and below that a one, two, or 4 digit date stamp. What year was your rifle made?