The key is in your own question: PRACTICE. The 6" 629 which I own by the way, will be of little or no handicap in my opinion. The 6" is a good compromise of sight radius and portability. When in practice my .475 with a little 4-3/4" barrel will stay in 3-4" at 100 yds. off my knees, (field position). I wouldn't want to bet on doing it right now, because I haven't been practicing with it enough. I think the 6" would serve you well.