Which weapon uses a gas tappet locking system?

• A. Benelli M4 Super 90
• B. SCAR-H
• C. AK-47
• D. M16

Answer: (A)

Gas tappet locking is a specific gas-operated action where gas from the barrel drives tappets that actuate the bolt locking and unlocking, allowing the weapon to cycle. The Benelli M4 Super 90 uses this design, a distinctive system that relies on those tappets to unlock the bolt and replenish the next round, contributing to its reliable cycling in a semi-automatic shotgun.

Other systems operate differently. The SCAR-H uses a gas piston system (often a short-stroke piston) rather than tappets. The AK-47 employs a long-stroke gas piston with a tilting locking bolt. The M16 uses direct impingement, directing gas back into the receiver to cycle the action instead of a tappet mechanism. So, the weapon that specifically uses a gas tappet locking system is the Benelli M4 Super 90.