Colt 1911 Sear failure?

[Snake6]

I just started having a problem with my Colt 1911 series 80 MK4...
Cocked and Locked and safety on... I squeeze the trigger and the hammer and safety falls at same time firing the weapon. (i've stopped carrying concealed this 1911 for that reason alone.)

I've read in a gun book that the problem is that the Sear is failing. Though it may be something else.....
So what needs to be done to fix this problem? Gunsmith?
Helpful info. wanted.

[larry starling]

Is the pistol stock or has it had some work done to it?

[spober]

OPPS i forgot to put in that tiny little thingy gizmo!a 1911 the allows the hammer to fall when the thumb safty is engaged is a sick puppy!is this phisicaly even possable?the thumb safty mechanicaly fits into a notch.its either on or off?

[Road Dog]

Gunsmith, without a doubt.

RD

[1911Tuner]

It's the thumb safety. Replacement is probably needed, though if it's not too far off the sear and made of decent steel, it can be peened and refitted.