Seeding and fertilizing alfalfa with concord air seeder

I Gothink 40 acres of ground to put into alfalfa this spring. I want to get it worked up nice and then hit it with our concord just barely scratching, it has 10" spacing but fans seed out about 4-5 inches. I also want to throw some people and k in one tank to get that out there to, just wondering if there is any seed burn issue? Also I'm thinking of seeding it twice at 1/2 rate to make up for any uneveness... any one have experience seeding alfalfa with a concord?

Seeding and fertilizing alfalfa with concord air seeder