3-20x50 SB PMII (std) MTC Lockable Problem

CS95 said:

this happens on the S&B DT turrets when you over torque the turret set screws. The over torqued screws create a raised burr. That burr contacts the turret cap and causes the turret screw to turn with the cap.
If you are mechanically inclined is a pretty easy fix. If not, you will need to send it in for service.

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1. Loosen 2x zeroing (unplugged head) setscrews
2. Remove plastic plug from hex of 3rd ( turret retention) setscrew using dental pick
3. Remove 3rd setscrew (you may have to very slightly lift the knob while simultaneously pressing the lock ring down a bit lower to clear, don’t lift it too much or the detent pins in the turret can pop out of their grooves and rotate and you can lose either the 0.1 or 1.0 mil clicks, and then you have to completely disassemble the turret to reset the detent pins.)
4. Apply a tiny bit of low or medium strength Loctite to the removed 3rd setscrew
5. Reinstall 3rd setscrew into knob, and while pushing the turret down tighten the setscrew until you feel it just barely contact the spindle
6. Loosen the setscrew approximately ¼ turn from the “light contact” position. It needs to be loose enough not to drag the spindle when you try to zero the turret, but tight enough the tip of the setscrew is in still engaged into the groove of the turret spindle so it prevents you from pulling the turret off the scope when you have the 2x “zeroing” setscrews loose to zero the turret. Right now it’s a good idea to look through the scope at something while rotating the turret to make sure the reticle isn’t moving… it will click, but the reticle should not move. If it is moving, the 3rd setscrew that you just reinstalled is still a bit too tight. Loosen it just a tiny bit more and try again. If the reticle isn’t moving as you spin the turret, everything is OK—let the Loctite set up.
7. Reinstall plug into 3rd setscrew.