If you are looking for 40 gr. bullets that will expand at .22 Jet velocities, good luck. My 5.7X28 FN will push them about the same velocities, and I can tell you the Sierra Hornet soft points open little, if any.
The factory, 40 gr. (Hornady) V-Max loads, however, open quite well. I'd look for that bullet for the Jet. E
