Fine if you use a proper bullet (barnes, failsafe, partition, TBBC). I would also limit your shooting angle in particular. Moose may not be tough to topple but they are large!!! With that comes a substantial shoulder area & massthat can soak up a bullet. So with that in mind I would suggest limiting yourself to positive shoot angles that lead to unobstructed vital hits. AKA broadside and slight quartering. I personally wouldn't take a raking shot on a bull moose with a 270 win, no matter what bullet I had in the tube!!!!

I have harvested moose and elk with a 270 (using either 140 failsafe or 150 NP). I would only take a vital open shot and my self-imposed max range was 250ish. I never losteither animal to the 270 but I will tell you I did have to let some walk as the shot was to iffy for my liking. However that is hunting, IMHO.

You said you have a 7mm rem mag, which happens to my cartridge of choice for the past number of years. This selection opens up more options in shot angles, distance and bullet selection. I personally would go with it over the 270, unless the 270 provides you with more confidence.

From personal experience no comparison when you talking moose and elk....just my 2 cents worth.