The 450 #2 is a totally different cartridge. The only common measuremnent is the bore size. Rigby made the NE first(1898) the afterwards the #2 came in designed by Eley(1903)
The #2 is alot bigger thus lower pressure.
Look here for the measurements of the cases.

http://members.shaw.ca/cstein0/riflelist2.htm

edit; With the new brass by Jamison and Hornady the 450 NE is cheaper to shoot. The #2 has very spendy brass made by Bertram and Hornbearer I think.

Last edited by AkMike1; 11/20/09.
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