NO, the .17 HMR and the .17 Mach II are not interchangable as the are made on differant cases.
The HMR is based on a necked down .22 Magnum while the Mach II is based on the .22 long rifle.
Ruger, Taurus and Heritage all make REVOLVERS in 17 HMR to name a few.
Hope this clears things up.