Some players find that using the Shrink Ray combined with a powerful weapon to be one of the best combos for dealing with tough enemies in the game.
It's very easy to get your hands on the Shrink Ray in The Outer Worlds. This is the science weapon that is the most easy to get, and all you need to do is to travel to Phineas' Lab after getting The Unreliable airborne. So just travel to his lab, then head to the main chamber where he is located. The Ray Gun is laying on a table just to the right of him. Loot this, and the science weapon is yours to keep!