3" 28ga. rounds are still being made. The ones I've had were 28 gram loads. Some of the Franchi 0/U 'International Skeet' guns in 28 ga. built on 12 ga. frames were chambered 3" and so marked. The 3" 28 ga. cartridges we've been getting recently are Fiocchi's. Cost was roughly $11/box. FWIW, Beretta has also chambered some 28's w/3" chambers. There are probably others. The Franchi's mentioned were made in the late 60's.