The Hornet and the .222 were introduced in the Royal Model in an action taylored to the .222 cartridge. Have not seen or heard of a Hornet in the Majestic or the Monarch actions which followed (short action for these was .308 length).
These came in a light weight and standard version - the light weight had an alloy trigger guard and floorplate and some metal removed from the action on the left side between the reciever ring and the rear bridge and has a lighter barrel. The action is the same diameter as the short and standard actions and stiffer than the Sako Vixen.
These actions are different from the later actions and the Herter U-9.
Mine in .222 is a delight to carry and shoot.