I have an old German sxs manufactured between 1913 and 1923. There is a slight looseness when held at the wrist and receiver and shaken with the chambers empty. However, if I put either snap caps or spent shells in the chambers the looseness is completely eliminated. With empty chambers there is no light visible between the breech and face. However, with snap caps in the chambers light is visible. I measured the breech to face gap with snap caps in the chambers and found it to be in the .004 -.005" range.
Would this be considered loose, off-face, etc?
Phil