600mm vs 700mm using slugs

I have no experience with slug. Never shot them due to the price being so high vs pellets. But I want to try it out. So my question is, is 600mm or 700mm better for slug? I've seen everyone who shoots slugs are using 700mm. Is 700mm necessary? I have the 600mm 25 cal impact. I choose 600mm over 700mm cause its more compact, easier to carry around without worry out bumping the barrel, also dont have to take off the LDC everytime I put it back in the case. So if I want to shoot slugs accurately. Should I just buy the slug liner 600mm. Or buy the whole 700mm kit? I want the best accuracy possible from my impact. Like 1/2 inch at 100 yards.
 
The 600mm liner is 1:20”, the 700mm is 1:21” so it seems the 600mm would be better. However, I’ve had better accuracy with the 700mm, not by much though! For you already having a 600mm gun and liking it short, it’s $110 vs. $400. I’d buy the 600mm slug liner and just find the right slug for it. The Nielsen 33.5 or Varmint Knocker 32.8 would be my top choices. With all of that being said, you’re not going to throw in a liner and start shoot 1/2 moa at 100yds. That’s an awful lot to ask for. It sounds good and a lot of people claim to do stuff like that but 1 moa groups at 100yds consistently, is exceptional. 

Stoti
 
Its odd , My buddy has a 600 Slug liner in .22 and that does not seem to shoot many slugs , if any ?? I was under the impression ( at first ) that you just stick the slug liner in and away you go , Turns out that is not the case at all ?? Please correct me if I am wrong , my buddy did just that and the gun did nor shoot a single slug . Its really odd ?





Rog