The serial number.
My grandpa give me this 3030 Winchester model 94 i need to know what year it was made
1955.
1973
1959
1966
Circa 1972.
1968
your Winchester model 1894 was made in 1974.
your Winchester model 1894 was made by Winchester in 1983-1984.
Your Marlin model 30AS was made in the year 1984.
To find the year that any Winchester gun was made, you just need to know which model it is and what the serial number is (the model number and serial number are stamped on the gun itself). Then go to this website and it will tell you when it was made: http://oldguns.net/sn_php/winmods.htm
With the serial number that you provided,your Winchester model 1894 rifle was made in the year 1940.