The Proof Marks are obvious forgeries too! Apart from the fact that they are just plain wrong the 'Not For Ball' mark was 1875 to 1887 and the 'Maximum' mark was 1896 to 1904. Not even researched it before adding the spurious marks. An English .410 just wouldn't be as heavy as that. Anyway, 1/2 ounce loads would not have come in until after 1913 here in England as all .410's prior to that had the 2" chamber for 3/8th. ounce of shot. What a Wally! Rigby's would not have turned out such a poorly finished firearm. The seller wants prosecuting. Lagopus.....