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For a custom AR-15 build, you’ll have to start with the upper receiver. Such receivers are present in both stripped and barreled front. But using a stripped version gives you an edge as it is suited for hunting. The barrel has to be either 16, 18, or 20 inches. Among all of these, the 20-inch barrel is the right choice. The handguards are in free-floating and non-free-floating versions. Employ a free-floating hand guard to achieve better results.
