read here for some stats; compared to 22 mag and 22 lr.
http://www.varmintal.com/17hmr.htm
come here to read a bunch of dudes opinions about it...
http://www.rimfirecentral.com/forums/
I personally don't use it too much anymore, it is too expensive for ammo.
but then, it is an amazing little round still going 2000 fps at 100 yds, that is faster than a 22 mag at the muzzle. with a 100 yds zero, it only drops 3 inches at 150 , and 7 inches at 200.
however i prefer the 17mach2, to the 17hmr, and it is 1/3 the cost, with only a 50 yd loss in trajectory. Plus it will fire the 17Aguila round, which is a 20 grain fullmetaljacket boattail bullet, and is good for not blowing up your small game.
That being said, the 5mm remington mag is about to come back out, and that will make all other rimfire ammo and rifles obsolete, for hunting purposes that is.
Basically it has the same trajectory as the 17hmr, but in a 20 caliber bullet the weighs twice as much, so it has half the wind drift of the 17hmr, at 200 yds, but still very little drop.
go here to read abou the 5mm mag...
http://www.chuckhawks.com/index2.guns.htm
http://www.varminter.com/
the new ammo is allready being made, and they also plan on a hotter round, a
32 or 35 grainer, doing 2500 fps, which is totally smokin hot!!!
That is like a downloaded 204 ruger round, which is typically doing 4000 fps.