The Belfast big man tipped the scales at a career-lightest 197.2lbs. English champion Askin also came inside the 200lbs championship weight, slightly heavier at 199.1lbs.
Physique-wise McCarthy is obviously benefiting from his first year under new trainer and former European champion Brian Magee.
Stablemate Anto Cacace [14(7)-0] also appears on the bill tomorrow night at the Victoria Warehouse, with the Andersonstown super feather weighing in at 135.1lbs. Opponent Leonel Hernandez [10(1)-15(5)-2] will weigh in later.
Should McCarthy win on the VIP Promotions bill tomorrow night, and he is a slight favourite with the bookies, he will secure a shot at the vacant title against Welshman Craig Kennedy next year.