I saw the movie "No Country For Old Men" with Tommy Lee Jones and Josh Brolin yesterday. It was one of the best movies I've seen all year. Tommy Lee (the Sheriff) was making an armed entry with his 70 Series Colt .45 (it had the Colt medallians on the grips) and he just cocked the hammer prior to entry, indicating that he was carrying one in the chamber with the hammer down. This is NOT the way to carry a 1911 .45 because an accidental drop could cause the gun to fire. My question is: What is the difference between the 70 Series Colt (no firing pin block) and the 80 Series Colt (with the firing pin block) in this regard. Are they both equally unsafe to carry with one in the chamber and hammer down?