That's too much, I'd guess.
RCBS makes a 22-250 mold that folks use for .223, and it is supposedly pretty good. I had a very hard time getting one and ended up buying a NOE 3 cavity of that same RCBS profile(Right around 60 gr with a gas check).
That being said, I only bought that for a very rainy day. It isn't hard getting a cast bullet through an AR, cycling the action and the velocity required to do so and accuracy with a cast bullet are kind of at opposite ends, though.
And you'll likely want to resize to .225, but it depends, as always.
I can only reiterate what I read when I decided to buy a mold, I have the equipment, but little experience. I'm sure someone will come along who has traveled that road. There is a smattering of discussion over at castboolits under the military sub forum about such things. And a couple pages out on the www about how well cast does through a bolt action .223