I'm fairly new to shotguns, having only done sporting clays until a month ago when I bought my M4.
I've been shooting mostly slugs, and well, the Winchester 1600 FPS 1oz Rifled Slug (X12RS15VP) only fits 4 rounds in the 5 round Benelli magazine tube.
My M4 H20 is 100% stock (no modifications).
NIce slug, shoots well, and never a mis-feed to date, but my Federal 2 3/4 Vitol Shok 1 1/4oz slug rounds fit 5, and my Armscore 12 gauge 00 buck fit 5, and other 2 3/4 have fit.
I just shot the Winchester slugs for the first time today and found out they don't fit 5.