5.56 NATO 62 gr FMJ Frontier® - Hornady Manufacturing, Inc

5.56 NATO 55 gr. CX® Superformance® - Hornady Manufacturing, Inc

Brownells Is Actually Selling Bulk Ammo Barrels in 5.56 and 7.62X51

410 Shotgun Ammo at Ammo.com: Cheap 410 Ammo in Bulk

Wolf Ammo at Ammo.com: Cheap Wolf Ammunition in Bulk

Which Rifle Round is Better: 7.62 vs. 5.56 NATO

This is why the US military uses 5.56mm ammo instead of 7.62mm

7,62 mm vs 5,56 mm