Picking the Best 6mm ARC Bolt Head for Your Rifle
Choosing the right 6mm arc bolt head is probably the most critical decision you'll make when putting together a new build or swapping out an upper. It's the heart of the rifle, and because the 6mm ARC (Advanced Rifle Cartridge) isn't just a "plug and play" 5.56 derivative, you really have to pay attention to the specs. If you get the bolt wrong, you aren't just looking at a jam; you're looking at potentially dangerous headspace issues or a rifle that simply won't fire. ...