The receiver will say Magnum, AND the serial number will end with the letter "M".
Since yours ends with a "V" it isn't a Magnum.
You can have the receiver converted to Magnum by having a gunsmith with the correct special riveting tools install a Magnum length ejector assembly.
In fact, the only difference between a Magnum and standard receiver IS the ejector.
Wilson Custom offers a "Remington Steal Deal" in which they rebuild your gun, parkerize it, put on new synthetic stocks, AND convert non-Magnum guns to Magnum by installing the longer Magnum ejector and a 3" chambered barrel.