Considering a new slug gun for deer season this year. The test barrels the slug mfgs use are 30" IIRC. What kind of muzzle velocity difference can I expect if I buy a slug gun with a 21" barrel? Thanks in advance.

*Note: Apologies if this has been discussed, I couldn't find it with the search function.

Shotguns use very fast burning powders and are not especially sensitive to barrel length, so you�re 21� barrel will shoot quite close to a 30� velocity wise.

Have you used a 20 inch shotgun barrel modified and coming as with an inproved cylinder.If so how well did it perform with rifled slugs?.If this is out of line and hijacking your thread ,my apologies.

I don't see any advantage to a 30" barrel other than possible recoil control. I have 2 slug guns, an Ithaca Deerslayer II with a 25 inch barrel and a Rem 870 with a 22 " barrel. Over my chrono,, the velocities are close to the same for all intents and purposes.