Most states have minimum calibers for deer. I know that a few don't. Howeverin most states the 22 or 17 would not be legal. That would be a good reason not to use them. In the two states where I hunt most, the 222 is the minimum. The hornet and any rimfires do not meet the laws. Where legal, those guns may be used and although I prefer the 25 caliber as minumum, thats just me.