a moose can be taken with almost any gun. the question is what will do the job right. You are faced with an ethical question here, and it is your responsibility to respect the animal enough to make the cleanest kill possible. while this is possible with a .270, the slightest error in shot placement could leave you tracking a wounded animal and perhaps not finding it. Personally, i would recommend at least a .300 just to minimize any risk of loosing an animal.