what kind of slugs should i shoot. i have a marlin 12ga bolt action rifeld. just got it last year and havent had a chance to try dif slugs yet. has anyone shot this gun and if so what slugs did you use and how did they work?

Lightfields seem to work in almost everything

Every barrel is different.........I would start with Win BRI sabots.....Hornady SST and pick another Sabot you might like and see which one the barrel likes.....

I also have the Marlin 512 Slugmaster.

It shoots Win BRI style very well. This year I switched to Brenneke 2.75" KO Sabots (a true sabot, not their hybrid style) because the Winchesters now cost over $11 a box. The Brennekes shoot real well too, and cost $8 a box.

I tried Hornady SST and they did not group well at all for me. I only bought one box, and maybe it was a bad shooting day, but with the cost of most of the fast slugs, I'll stick with the Brennekes.

Shoot as many different types as you shoulder and budget will allow until you find one that gives you acceptable accuracy for the shots you anticipate taking.