Im considering a custom revolver in 454 Casull. Itll be mainly for attacks while hunting but for sure Ill carry it on occasion around town and bring it to Bar-B-Ques. I have a 7 1/2" already so I want something shorter. So Im wondering how short can I go and still get 454 performance (or at least better than 45 Colt)?

Ive seen pretty short options; but I wonder at what point do I turn 454 into 45 Colt? Id like to go 4.5" or maybe even 4". Is that reasonable?