Should You Get a Gas Piston or a Direct Impingement AR-15?
The AR-15's users are divided on whether the weapon should employ a gas piston or a direct impingement mechanism. Each choice has its own set of benefits and drawbacks. Just as with the gun, it all comes down to what works best for you. Because of the AR-15's versatility, you may choose either one or the other. Because the direct impingement and piston-driven systems function independently of the lower receiver, you may alternate between them at a whim. For example, it might be possible to mount a piston-driven upper receiver on a gas piston AR. What differentiates the two, and...