Bypassing gates, such as this one shutting down MCB-6, is prohibited on Marine Corps Base Quantico for safety reasons. For example, MCB-6 runs directly behind the targets on Range 11, among other possible surface danger zones. - Bypassing gates, such as this one shutting down MCB-6, is prohibited on Marine Corps Base Quantico for safety reasons. For example, MCB-6 runs directly behind the targets on Range 11, among other possible surface danger zones.