First, I don't use the splatter method of forum posting but I will be posting this anywhere there might be an answer. Does anyone have any information on how long a 20 gauge sabot barrel has to be to burn the powder and stabilize the sabot? I'm old enough to remember when slug barrels were shorter but back then the slugs were Fosters not sabots. The Mossberg brand I use is now standard at 24" and my friends and I have had nothing but trouble with group size. For whatever reason the 12 gauge seems to work fine. To be clear we have been through about 6 of the 20s. I have the last one now and will probably buy it if there is a chance I can mod it to work. The reason to fixate on barrel length is a history of using H.D. barrels or "riot guns" for deer hunting pre sabot. It seems that the closer the barrel ends to the mount for the magazine tube the more rigid the barrel stays and the better the group. My thoughts so far are either 20" or all the way down to 18 1/2" Any information about velocity or groups from someone who has a shorter barrel would help.