Any info on my pistol would be great

[MackallResident]

This is my post deployment gift from my Father. He knew I wanted one similar to his 1911, and I have never seen one with the same rail as mine. Anyhow, here it is: Springfield Armory Operator .45
Any info on this type of pistol would be greatly appreciated.
I have fired around 1k rounds through it since last January, and with regular maintenance it seems to be my favorite.

I have been able to take the barrel out of the slide though, that is my major issue