MDOLson:
It is my understanding that the .17 HMR is a .22 rimfire magnum necked down to .17 caliber, so unless I am wrong, and if I am you can be sure I'll hear about it, any .22 rimfire bolt should work with the .17 HMR.
JMHO
Dave
Note: After posting, I measured the rim diameter of a .17 HMR and a .22 RF. The .17 HMR measured .289" and the .22 rf measured .274. I still believe that the .22 rf bolt will work