Thread: When you dial

With regard to tapping, this used to be recommended 30 - 40 years ago. You use an empty cartridge case.

Even now it’s common to see, when sighting in, that an adjustment apparently makes little difference to the fall of the next shot but after 3 or 4 more the group settles on the new mpi as you’d hoped. There are several possible reasons for this :

Moving a few 1/4 MOA clicks in the hope of correcting a group that’s 6” out at 100yd. (This would really need 24 clicks so 2 or 3 is homeopathic .

Adjusting on too few shots for the grouping of your rifle . eg firing 2 shots 1” apart from a gun that really a 2” grouper and expecting 4x1/4 MOA clicks to bring it to a zero. In this situation you don’t really know where your group centre is. The tendency for subsequent shots to fall closer to the true mean pint of impact (regression to the mean) will make any random adjustment appear effective as long as it’s a small one. Most often your gun was shooting fairly close to where it should and small adjustments just shift that centre around confusing you and undermining your confidence in gear and skill.

Third is the truly sticky scope. This is not too uncommon in my experience. On most hunting rifles, with capped turrets, adjustments are made only rarely and the spring can be weak and lubricant a little gummy inside so the reticle doesn’t move at first but will after a couple of shots and the tapping is meant to encourage it. It’s pretty hard to be sure this is happening because it’s bound to move immediately if you try it a second time ! With scopes that are regularly dialed back and forth I think this is less likely and newer scopes all claim to have “improved” spring systems.

Personally, I wouldn’t like to tap my scope regularly with something metallic but there are good reasons why people do.

Another aspect to this is that it’s one thing to wind on 80 clicks and be pleased the group moves closer to 20“ than 19. and another thing to find your tweak of 1 or 2 clicks truly Centers your group in the 10 ring. This sort of reliable response to small adjustments when sighting in is beautiful when you experience it . It’s largely a matter of gut intuition when you realise that your scope is actually doing this.