While I have never had a .22 Hornet, I have had several .223 Contenders over the years. You have already been given some excellent advise, and I would have to place my vote also with the Super 14 .223. I have had a couple different Contenders with 10" Bull Barrels chambered for the .223 over the years, and have to agree that for this cartridge the Super 14 version is the way to go (especially if you are restricted to Factory Loads).
I am primarily a Varmint Hunter, as well as an avid Handloader. I have settled on 3 loads for my Super 14 .223 Contender uses.
One uses a 40gr. Nosler Ballistic Tip Bullet loaded to roughly 2900 FPS with Alliant Blue Dot Powder. This is an excellent general purpose load, it is amazingly accurate, and super mild to shoot in terms of Recoil and Muzzle Flash & Blast.
Another load uses the same 40gr. Nosler Ballistic Tip Bullet loaded with H-4198SC. This load is also amazingly accurate, and churns up 3250 FPS Muzzle Velocity.
The third load I typically use in my .223 Contenders consists of a 52gr. Speer Flat Base Hollow Point with either H-322 or W-748 Powder. Normal muzzle velocities with this bullet run around 2850 FPS. Accuracy has been quite good, and this bullet is quite explosive on small varmints also.
I have used all three of the above mention loads on Prairie Dogs, as well as a couple different commercial reloads. I have had good results with the Ultra Max Commercial Reloads with both the 40gr. Hornady V-Max Bullets, 40gr. Nosler Ballistic Tip Bullets, and the 52gr. Speer Flat Base Hollow Point Bullets. My handloads squeeze out a little more velocity than do these commercial reloads, but I have found these commercial reloads to be quite accurate in the Super 14 .223 Barrels I have used them in.
Good luck with your project.
Larry