I like to make simple guns, an interesting example is the Cobray Terminator shotgun. The Cobray is a single shot shotgun. It has a fixed breech with firing pin, often mistakenly called an "open bolt". Actually the Cobray is a unique system that is neither open bolt nor "blow forward". To fire the Cobray a shell is placed into the open port and pushed into the barrel. The barrel is under spring pressure and when released, is forced rearward into a fixed firing pin in the breech plug. The round fires and barrel is blown forward. To load, the barrel is pushed forward and rotated into a locked position A round is inserted, and the barrel is unlocked, much like an MP5, by pushing the charging handle downward. The barrel then moves a small distance rearward where it is caught by a catch. Pulling the trigger, drops this catch allowing the barrel to move rearward under spring pressure and fire. In the video below, you will see the host complain about misfires and light primer strikes. The Cobray actually has an adjustable firing pin whose depth can easily be adjusted...it is simply a threaded firing pin locked in place with a set screw. My improvements include a more ergonomically placed charging handle, an extractor, muzzle brake, and sturdy folding butt stock. A marketing failure, and universally hated, the Cobray now commands collector prices of around $1400.
The original Cobray
The Cobray Terminator
Work in progress.
Possible trigger housings.
The original Cobray
The Cobray Terminator
Work in progress.
Possible trigger housings.
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