Do I need to be concerned with lead fouling while using Lightfields with a rifled barrell?

no they are saboted, i shoot the 3" hybrid elites, and can clover leaf @ 100, no fouling

I never had a problem with the Lightfields, and I too had good results. I am try Hastings Laser Mag Sabot Slugs this year. Went to the range and made one big hole at 100 yards, with my Mossberg 835, shooting their 3"ers.

Sabots will not cause lead fouling, but they can cause plastic fouling so you still need to clean the barrel with a good solvent.

Paul