Try upping the charge. I run the 40 gr vramagedin hp from my 22hornet. Which is the cz527 with a 16" twist. I'm loading up 12.7gr of lilgun for 2990fps. Those hornets are VERY finicky. Working in 0.1gr increments can make a big change in grouping. I light mine off with the cci small pistol primers and give them a good neck crimp with a Lee factory crimp die.
A big problem with the 22 hornet, is that because of the thin case walls and almost straight body, the timer igniting can cause the bullet to jump before the powder ignites. Causing two pushes on the bullet causing irrational grouping. this is made worse with light bulleta that have less resistance to the primers push. A couple of fixes for this are, a good crimping and using primers with a lower flame. Remington makes the 9.5 primer size that is made for the hornet. Has the flame of a pistol primer but the shell of the rifle primer. So you get the gentle push and the jacket that handles rifle level pressure. When using lilgun you can get by wth pistol primers because it runs at such low pressure in a 22 hornet.
I run the pistol primers in my hornet using lilgun, except for the firing pin dint, it looks like a new primer all the way up to a 13gr charge (at the mouth rim with Ppu brass)with a 40 gr bullet. I had a problem in mine using lilgun with HORRIBLE grouping and 200+fps speed spreads, until my charge got high enough to stabilize the burn rate. At too low of a charge for the bullet, you run into sporadic burn rates. Getting velocities from 2750-3100 fps with the same charge. Once I hit a certain point of charge, the speed spread and grouping dropped dramatically. From 3moa and 250+fps down to 1/3moa 20fps spread. And be aware that thes little cases have NO room for we're when it comes to loading. You have a 0.1gr charch window and 0.01" seating depth variation without affecting grouping.
I think I use more dies and precise loading techniques than I use for any other rifle I own. But it's also the most fun rifle/cartridge combo I have to shoot.
I hope this helps,
Kyle