Thomas, yes sir, the bottom barrel in the picture is rifled. Hope this helps, more specs here if interested............. Pump Action Shotgun,
20 Gauge,
6 Rounds (5, 2-3/4" shells in the magazine tube with 1 in the chamber),
22" Vent Rib Barrel with Twin Bead Sights
Vent Rib Barrel Threaded for AccuChoke Choke System,
24" Fully Rifled Slug Barrel with Rifle Sights
3" Chamber (accepts 2-3/4" and 3" shells),
Top Mounted Safety,
Dual Extractors,
Twin Action Slide Bars,
Black Synthetic Stock,
Blued Finish,
Youth Length of Pull 12"-13",
Overall Length 39.75"/42.75",
Weight 5.25 lbs,
Includes:
AccuChoke Set: Full, Modified and Improved Cylinder
Length of Pull Adjustment Spacers

Yes sir, the 24" barrel is rifled. You would want to use Sabot Slugs with it.

Thomas, yes sir, it is a 24" Fully Rifled Slug Barrel with Rifle Sights.
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Full Specs -
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Specifications and Features:
Mossberg 500 Youth Super Bantam Field and Deer Combo 54250
Pump Action Shotgun
20 Gauge
6 Rounds (5, 2-3/4" shells in the magazine tube with 1 in the chamber)
22" Vent Rib Barrel with Twin Bead Sights
Vent Rib Barrel Threaded for AccuChoke Choke System
24" Fully Rifled Slug Barrel with Rifle Sights
3" Chamber (accepts 2-3/4" and 3" shells)
Top Mounted Safety
Dual Extractors
Twin Action Slide Bars
Black Synthetic Stock
Blued Finish
Youth Length of Pull 12"-13"
Overall Length 39.75"/42.75"
Weight 5.25 lbs
.
Stay safe & have a great day!

Hi Thomas and welcome. Yes, it is a 24" Fully Rifled Slug Barrel with Rifle Sights. Cheers and stay safe!