Hi,Im new to this forum and have a question about my Colt Trooper MKIII (22LR).What is the allen key adjustment for, located under the back of the trigger? Please describe what adjusting this will do.Thanks
The Allen screw is a trigger over-travel screw that the factory fitter could use to adjust the amount of over-travel of the trigger.
It was never intended to be used by the owner and was pre-set to the exact required adjustment at the factory.
I do NOT recommend re-adjusting it.
Unlike other guns fitted with adjustment screws, this screw was intended strictly as a factory method of properly fitting the action, and it's set to a close spec.
Re-adjusting the screw can cause the action to fail to operate properly, and can actually cause the trigger pull to get heavier due to interference of internal parts.
The factory Loctited the screw in place, and turning it can potentially cause the screw to move, jamming the gun.