The front sight blade is retained by a cross pin - using a punch of the proper diameter drift the pin out going from left to right. The sight base itself also has its own retaining pin - same removal procedure. The base can then be tapped forward off the front sight base key - I use a hardwood block for this. Removing the key from its cut in the barrel can be interesting, and I wouldn't recommend trying if you don't have to. In those instances when I've had to remove the key, I'd turn the barreled action upside down, clamp the key firmly between the jaws of the bench vise, then gently tilt the barreled action up and away from the captured key. Hope that helps.