went shooting with my in-laws yesterday. they brought some of those winchester 45 gr hp varmint factory loads. i think they're the same thing you're using, Cajungeo. the box says they are loaded for 3600 fps. anyway, i was impressed with the groups we got. didn't really fire shots for record, just blasting away. i guess i'm gonna have to get some and test them out. i know i got a 1"-10" twist, so i thought i'd get bad accuracy with that round.
usually i shoot handloads 63 gr sierra sp with 23 gr blc-2 for accuracy.