The name "Sport King" was used on several different High Standard's Could you post a picture for better identification?
Anyway, if it's a late model look at the front of the frame and you should see a botton/plunger sticking out under the barrel. If so, clear both the magazine and chamber. Then re-insert the magazine. Pull back the slide to latch it open.
"Bump" the front of the plunger against the edge of a workbench. Then push it inward while lifting the barrel straight up. It will come out of the frame.
While holding onto the slide, unlatch it after removing the magazine. Run it forward and off the frame.
Reassemble in reverse order.
If this doesn't make any sense it's because you have a different Sport King. In that case more information will be necessary to identify it.