Brian. You might not have realised, but 5p groups at 25/30 yards will get you a long way in HFT. There are some 15mm kills, but most are 20 or 25mm, up to 45mm. Much bigger than a 5p (18mm).
The main skills (in my opinion) are range finding, judging the wind, and being able to shoot from different positions. All transferable from hunting. You might surprise yourself with how well you do if you gave HFT a go
regards
Dan