I got a call from a friend that was buying his brother a new Remington 870, he wanted to know if he should get the 28" or 30" barrel.
I figured that since it'll primarily be used for waterfowl and he won't be carrying it on long hikes he should go for the 30" and gain a few more fps.

Did I give him the right answer? How much difference will 2" make.

Thanks guys.

IMHO the velocity issue is mute. The 30" bbl will be better for swinging throught he target. That is the true advantage of a longer shotgun bbl. Just my $.02

IMO the 30" will swing a little smouther . BUT if you lay out or hunt out a tight blind th 26" is the best .
I shoot a 26" 870 express supermag

I don't think the same rules for centerfire rifles are the same for shotguns. They use much faster powders and accelerate much faster than a centerfire rifle. Thats the reason for the very thick breech but thin barrel at the end. It may be true for slugs. But even those use very fast powders.