If you're after cheap projectiles for .303, be sure to try the hornady 174gr RN. They're a genuine .312 projectile, and work a lot better in worn barrels. They aren't much good beyond about 200m but are good within that range.
For powder, most of the service rifle guys run 2206H or 2208 with good success. Just a thought if you aren't too committed to using 748 or 760.
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