Welcome to GBO!! Most that shoot factory ammo and many that can't find a handload that shoots as good, shoot the Winchester Whitebox 45gr JHP, me included, sub moa is the standard for this ammo and at $14 for 40rnds, priced right for good shooting factory ammo. It's not fur friendly tho from those that have shot coyotes with it.
You'll do good to use 55gr or lighter bullets, some will shoot 60gr-64gr bullets ok, but even the 1:9" twist barrels don't like the heavier bullets from all reports here.
There are several recent threads on .223 loads, look back a few pages to find those, the search function is disabled, hopefully for not much longer.
Tim