Dose it act normal with out ammo? No ammo pull trigger and hold. Pull chars handle and do you get a reset and hammer drop? If so load one round and see if it lock back on empty mag.
It is a long read but great info to have. This is from AIG gun smithing.
Determining Front Sight Height
Let's face it, for most of us, math is not one of our favorite pastimes. Well lucky for you, I spent a great deal of my misguided youth awash in the stuff.
Here's the problem - The front...