Hey Doug- I love Martinis too. Mine is a HMR with a GM barrel. With 17gr. VMax bullets (doesn't matter box colour), she'll put 5 into 3/8" at 100meters ona great day, and 1/2" to 5/8" most days with a little wind.
: We use our HMR's to 240 yards, then use the centrefire .17's from there on out. I don't think the HM2 can compete. We use head shots to 200yards and switch to chests for longer range. My buddies Marlin that I lapped for him is almost as accurate. My own Marlin will only hold 1/2" at 100 meters with some groups out to 3/4". Accuracy is not a problem. My Martini opens to 1" with TNT's - it hates them, but the Marlin will hold them with Vmax - go figure. There are 109 yards in 100 meters.