top gun 77Externally, the 77 have an updated desn, shifted mag well and a buffer tube that allows quick spring change. The 77 is now using power stock desn where the spring runs all theSet 30 years after its predecessor, it follows Maverick's return to the United States Navy Strike Fhter Tactics Instructor program (also known as U.S. Navy-Fhter Weapons School - TOPGUN), where he must confront his past as he trains