Liam Kinch registered a half century to help anchor the 1s to 181 for 8 from their reduced allocation of 39 overs, with 11 being lost due to rain.
His knock of 59 came from 66 balls and included six fours as he shared in stands of 32 with Ajay Khunti (8), 25 with Chris Yates (11) and finally an unbroken stand of 55 for the ninth wicket with Aaron Smith (23 not out from 25 balls.)
The Cropston top order surrendered meekly as they crumbled to 46 for 6 inside 20 overs with Smith (3-21), Harry Bates (1-25) and Ryan Dawson (1-31) giving Dave Torr's men a brilliant start with the ball.
Their momentum was checked by a stand of 81 from 93 balls between Nehag Pravin (63) and Dan Hickinbottom (26) to take them to 127 for 7. Ellis was wicketless at that point and soon set about righting that with a devastating spell of 4-10 in three overs.
He accounted for Dan Hickinbottom, caught by Andries Gous, six runs and a leg bye followed during the rest of the over before the veteran seamer combined twice in two balls with Khunti to dismiss Pravin, Alex Thompson (1) and then rearranged the furniture of Alfie Loakes to complete his hat-trick and seal a welcome 25 points for Sileby ahead of their upcoming clash with league leaders Rothley Park next weekend.