I have done it (my 44-40 is 101yrs old). Killed a black bear with it too. I use factory loads.
I can usually get within 100yds of deer where I hunt so the 44-40 is just fine.
I dont know if its worth scoping a 44-40 tho...Id say its a 100yd type rifle.
I think there is a 101yr old 44-40 on the EE.......? lol