alright I haven't read the whole thread so forgive me if I repost old information.
the no4 MK1 is a combat rifle from before the age of optics so none of them have scope rails except for the very expensive and hard to find sniper models. therefore you will either have to use Iron sights or take it to a gun smith to have a rail mounted. the open sights were set to hit point of aim at 300 yards so you will actually be hitting several inches high at 100 yards.
most will hold hunting accuracy but some may have been shot too much and the barrels may be shot.
303 brit is comparable to 308 Win for hunting and due to a heavy number of enfields that were imported following WWII there is a great deal of quality hunting ammo available for 303 brit.
short and simple answer, your new enfield is more than capable of killing a deer at 200 yards but you may not have the skills to make that shot with open sights. if you keep within 100 yards and understand that you have to hold low on your shots then the enfield NO4 MK1 will be a fantastic hunting companion.
AH DAGUMMIT!!!!!!! I FELL FOR ANOTHER ZOMBIE THREAD!!!!!!
ignore my complete lack of capitalization. I still have no problem correcting your grammar.
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