Just bought a Impact Mk3 Compact .22 in April ATN 4K 4×14 Hand held thermal Portable compressor Moved up from a Beeman R1 .177 I want to focus mainly on rats, starlings and pigeons in barns at night. Shooting Crosman 14.3 HP ($10.00/500 count) 20yrds max What FPS would you recomend for...