mine will pick up a BB gun (350 fps),,,,,I dont do subsonic rifles(whisper etc,,) but it should get one of them if it will do a BB gun,,,,I use it routinely for 300 mag--06--243--BR's etc,,,,this radar unit is unbeatable for convenience and it does not affect the bullet impact in any way,,,you just have to read the instructions and tinker with it a lil',,,,,Roger
https://www.facebook.com/photo.php?...998.1073741826.100002762413508&type=3&theater
here is a photo of my home made lab radar base,,,it can be tilted up or down and turned left or right ,,the mark on the center helps align it with the target and the bullet path,,,,plus a convenient place to put the battery pack,,,and note pad and pencil,,