I carried my dad's carbine in 30 caliber for the first year that I deer hunted. Never got a shot that first year, but do remember my dad and grandad telling me to wait for a VERY GOOD SHOT and not to hesitate to touch off more than one round if I could gain the visual aim point again.
In retrospect, the round is perfectly capable of taking SMALL deer with regularity, at short range, with quality SOFT bullets, and if in the hands of a marksman. So, I would not recommend the 30 carbine round for deer in general. Numerous other rounds that are far superior.
Very fun gun to shoot though, the m1 30 carbine.
Since my dad still has his carbine and many, many surplus rounds ((lots) of 30 carbine ammo, I've considered buying the Ruger Blackhawk model in this caliber. But NOT for use on deer (unless I was attacked of course)