One source shows the maximum chamber pressure of the 17 HMR to be the same as the 22 WMR, at around 25,600 psi.

The 1915 Favorite wasn't offered with chamberings that reached that chamber pressure level.

Hopkins and Allen offered a model No. 3925 that was chambered for the 25-20 Singleshot cartridge, but you'll have to dig up the original chamber pressure for that cartridge as it was loaded at that particular point in time to make a comparison.

From what I've read, CCI is the only outfit still making the 17 HMR (for both the CCI and Hornady labels), but the Mach2 seems to be tail-end Charlie to both 22 RF and 17 HMR production.