I have the S&W 8-3/8" barrel 647.
I splurged on it when I went looking for semiauto pistols and semiauto rifles in 17HMR, and didn't see any (semiauto pistols) or any I liked (Rem 597, I want a heavier barrel than that). I had wanted a 22 mag revolver for a while anyway, and the 17 is the same power. The Taurus was $200 cheaper, but I liked the longer full-lug S&W barrel. And I figured that even if I didn't like it, it's the first-year of a totally new caliber, so it should hold its value well (I am guessing?).....
-I am probably hitting around an inch at 25 yards off a rest and with a (cheap+lousy) BSA 2X scope. I say "probably an inch" because I am badly out of practice and can see I'm pulling many shots off-target. I only shoot paper so terminal performance isn't real important to me, but there's an online test of this gun somewhere clocking right around 2000 FPS.
Most others I meet and read online are getting the Taurus revolvers. I do see lots of different rifles though.
......
-And if you have the need to thump animals regularly, I still say you'd do better with a 22 mag, just for the different power and bullet choices available. At the time of this posting, there is only one .17HMR load out now (packaged under three different names), it's 16.7 gr at 2500 FPS from a 20" bbl.
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