Well I just got back from a 4 week trip back to UP Michigan, just above N/E Wisconsin, and had plenty of opportunity to shoot that rifle. I used the CCI 17 grain to more or less break the gun in, had two of my sons to help with the chore. Incidentally while up in the area I had the opportunity to purchase some Hornady 20grn XTP, and a couple boxes of Winchester 17grn Varmint Polymer Tip, as well as a box of 200 17grn CCI A-17, which were supposed to be 100 fps faster than there original. Well once we placed the target out to 100 yards, which was as far as we could go due to the brush not yet being cleared, I noticed that the higher velocity CCI A17 proved to be the most accurate, placing the 7 round magazines to make one little raggedy hole, with either me or my sons doing the shooting. Note it was a very still day, and the high temperature only reached in the low 80's with very little humidity.
The least accurate was the Hornady 20grn XTP, however they would still group under 1" at that same range 100 yards, the other the Winchester and the regular CCI all shot very close to the most accurate CCI A-17, but had at least 1or2 fliers,(all well w/I a one inch group) but then again it might have been due to the barrel getting dirty. Note the trigger was really bad when we first started shooting, but lightened up considerably after the first 100 or so rounds. Note when I got home I checked the trigger with my gauge and found it breaks right at 4#'s, so I don't think I'll even mess with that. Over all I'm really satisfied with that little plinker