Forster 223 WSSM seating die. Brand new 223 WSSM Forster Ultra Seater includes an ultra accurate micrometer adjustment. This micrometer adjustment allows you to adjust bullet seating depth from .0005 inch to .001 inch increments, and makes switching bullets easy - just dial back to your previous recorded setting. Forster Ultra Seaters make fine tuning your bullets to the lands of your rifling simple.