Bring salted water to a boil and cook potatoes until fork-tender, about 30 min. Drain and cool.
Hard-boil eggs. Cool.
Cut cooled potatoes, pickles (dill is best), celery, onion, and eggs into small chunks. Put in large bowl.
In separate bowl, combine mayonnaise, mustard, vinegar, and dill. Wisk till mixed and pour over potato salad. Season with salt and pepper.