The 525 is the latest version of the Browning Citori O/U. Generally speaking, O/U shotguns do not have triggers that are easily adjustable by the owner. Usually, this requires the skill of a good gunsmith who is knowledgeable about this particular gun. You might contact Browning about it, or read their website about the features of the gun, or, as a last resort, you can always read the owner's manual. :? :lol: