A friend has asked me for help identifying the manufacturer of an older Colt 1851 Navy. It has a brass frame, backstrap and trigger guard. It has a stamping on the right side of the frame, barrel and cylinder that says 'PN'with a small logo over it that looks like a star in a circle. Beside that logo in the frame in larger letters is XX7. The bottom of the backstrap has a nearly rectangular logo that looks like a G with a B inside it. To the right of that is stamped Italy and capital letters 'FIE'. There is a 5 digit serial number on the bottom of the barrel (445XX) but that is not stamped in a corresponding position on the brass frame (unlike my new Uberti 1860). My new Uberti has the same PN with a star logo over it so could the Navy be an older Uberti. Another question, on the Navy the barrel is loose to the frame with the wedge all the way in. Is there and easy fix for this such as an oversized wedge? The gap is probably more than 60 thou so I wouldn't want to shoot the gun like this. Will appreciate any help and info.