Got screw

[Giddaymate]

Got a question regarding a good old model 54 Ive got - what excacly does this screw here do?

[Tim S]

I think it tightens the frame around the elevation screw to account for wear in the threads.

[mtncwru]

I think it tightens the frame around the elevation screw to account for wear in the threads.

Pretty much. You can use that to fine tune how stiff your elevation knob feels. If you do that, I would recommend using a screwdriver with a blade that fits that slot perfectly (I found a set at Brownells), with the largest handle you can find. The sweet spot for that screw's tightness is extremely small, and the finer you can adjust that the better. It is entirely possible to tighten it to the point that you cannot move your sight, or loosen it to the point that it has slop. The difference between those two settings on mine was no more than an eighth of a turn.