Iron sights

[tbonesmith]

The foresight does have a very fine cross pin, and when you remove that, the block will move forward on the key with some gentle tapping with a hammer and a protective block.
The rear sight base has has a fine cross pin and also a little screw that locates the sight at the back of the base, under the ramp. When you remove these 2, the rear base can often be driven forward, but are also often too tight to be driven fwd without risk of damage, so I find that if you vice the barrel( with protection, blah, blah) then twist the base on the barrel with some good parallel jaws wrench, or even a very good shifter, it will free it up so you can drive it off fwd.
A bit of heat can be helpful.