My experience is with 22-250 which compares closely to the 220 swift as projectiles go. I have had great success with 60gr spitzer soft points. I would not go any lower than 55gr and 60gr will probably be the heaviest you can go unless the rifling is tighter than 1:14. Stay away from the ballistic tips and those designed to be more explosive than standard soft points. Copper solids such as those offered by Barnes are also good choices. I have a unique perspective on using the larger .22s for deer hunting as my home county once did not allow anything larger than a .22 cal. for deer hunting. The 22-250 and 220 swift proved themselves very effective deer rifles for more than 20 years.
The mightiest oak in the forest was once only a little nut that stuck its ground.