Question about the sights on my 625JM

Just picked it up today and have a question about the front sight. I notice that it has the standard, pinned blade and in this case with a gold bead (not sure yet if I like it or not). In the front (at the muzzle) there is a hole in the ramp approx. 3/16" in diameter. Looking through the hole I see a chromed pin that is larger in diameter than the cross pin that goes through the ramp. Looks somewhat like the quick change front sight on a GP-100. Is this a similar quick-change set-up? If so, how do you change blades?

Thanks,