0
That is a bit problematic. This model was rollmarked with the caliber designation on the top of the barrel immediately forward of the receiver. The other barrel markings should be: MARLIN FIRE-ARMS CO. NEW-HAVEN, CT. U.S.A. PATENTED.OCT.11.1887.APRIL 2.1889.AUG.1.1893 It is possible that your original barrel has been replaced, or perhaps the gun has been heavily refinished with markings obliterated during polishing. Either way is bad news. If you do not find the caliber markings, the only way to truly tell what caliber it is would be to have a gunsmith make a chamber cast. The original calibers offered in that model were .25/36 Marlin, .30/30, .32 Special, .32/40 and .38/55, however if the barrel has been replaced it might be chambered differently. If you can send some good clear digital photos of the gun, especially of any markings on the gun, we can tell immediately if the barrel is original and/or has been refinished. sales@countrygunsmith.net Calibers on these early Marlins are often faintly marked just in front of the frame, on top of the barrel. You will need a magnifying glass to read it. If it indeed wont show, then you need a gunsmith to check the chamber with gauges or a chamber casting of Cerrosafe.
