I have both and find the 17HMR to be way better. The main reasons are longer range and more explosive on impact. I use it to shoot small rodents and it's a 200 yard gun! The 17 gr bullet generally explodes on impact and really knocks them down. So IMHO it is way better.
The only applications where 22mag is better are shooting heavier bullets in the wind or when you need more stopping power.
I would not consider getting a new 22mag. Its 17HMR all the way. What do you think?
For your intended uses maybe but you are brushing a large stroke and have obviously not shot a lot of stuff bigger then small rodents. I'd suggest keeping it that way. Ever think someone else may have a different application than yours?
Bottom line is the Hummer does have a great niche but it does not include killing larger small game like coons, fox, etc. reliably. Don't tell me yest it can cause you head shoot stuff. That is not a gauge of a cartridge.
The 22 magnum is a better tool overall...
