I had a 44-40 and it was a great shooter. Very accurate. As far as crushing cases, it was very rare. I crushed no more than 2 or 3 cases. Just be observant when case is entering sizing die and have a slight bell on case mouth so the bullet will not crush case when seating the bullet. Normally, a 44-40 uses a 427 or a 428 sized bullet where as a 44 Special uses a 429-430 sized bullet.
I tried to load a 429 sized bullet in mine but they wouldn't chamber. From what I understand, some 44-40 cylinders may chamber a 429. The only bullet I loaded in mine was the Remington and the Winchester 200 grain jsp which if I remember correctly was 425 diameter. They shot great in my Colt. I wanted to try a 427 sized lead bullet but they were scarce when I owned mine.
Properly loaded, it would be fine for either hunting or sell defense. I had a Speer mid nineteen sixties manual and the load data at that time was extremely liberal. I have no doubt that the hotter loads would have dropped any deer.
Some of the expects on the forum will have a lot more info on the 44-40 than I.
Forgot to add that the biggest problem to me in reloading 44-40 was having to lube the cases and then removing the lube after loading. A lot of people frowns upon doing this, but I would run them in my vibrator for a few minutes to remove the lube. To me, that was no worse than flying ammo halfway around the world in military aircraft and hauling in the back of deuce and half trucks.