I took another very close look at my new model 29 with the 6 1/2 inch barrel. Again, my pin is exactly like yours. If you look at the other side of the pistol you will see the pin is flush so if you tried pushing that pin through it would just protrude from the other side. After looking at the protruded side under a magnifying glass it seems that the protruded side of the pin is actually the head of the pin. I would not advise trying to push that pin head in without consulting S&W first because I really do think that pin is sitting exactly as it should be. I think that head is meant to protrude and you could screw up your pistol trying to tap something in that is not meant to be tapped. Just my two cents.