The Welshmen put Warwicks into bat and had early success with Poonia and Darren Maddy both making four runs.
Tony Frost could only add 23 to the total which became 86-4 when Jon Trott became Shantry's third victim.
Jim Troughton and Tim Ambrose came to the crease and put on 101 for the fifth wicket with Troughton making 54.
Ambrose continued until the close making 86 not out from 131 balls and Neil Carter was also unbeaten on 46 as Warwicks picked up two points for being 270-7 before play ended early.