Notch
App of the Day
from the creators of 
murmur
Layered
A sight change fixes one thing: a group whose centre is in the wrong place. It does nothing for a group that is too wide, and chasing a single wild shot with the sight moves every good shot off centre.
Adjust for the group, never for a shot
Find the centre of the group first. If one shot sits well away from the rest, leave it out and find the centre of the good shots. Then measure how far that centre is from the middle of the target, up or down and left or right.
Which way to turn
The rear sight moves the way the group needs to move. If the group is low and right, it has to move up and to the left, so the rear sight goes up and to the left.
Read the markings on your own sight before you turn anything. Some sights are marked for where the shots are landing. On those, when the group is at the left you turn towards the L arrow and the group moves right.
How many clicks
Sights move in clicks, and each click moves the group a fixed amount at a given distance. Divide the distance the group has to move by what one click does, and round to a whole click. The sight calculator does that sum in MOA, mrad or millimetres.
When to leave it
One group off to the side is more often technique. Notch suggests a sight change only when the group sits more than 3 mm off centre across a whole competition card. Anything less, look at the group patterns first.
After you adjust
Shoot a five-shot group to confirm the new zero. If the offset is still there, check your natural point of aim before you add more clicks.
Updated 11 November 2026.
Questions
Which way do I move the rear sight?
In the direction the group needs to move. If the group is low and right, the rear sight goes up and to the left.
Should I adjust my sights after one bad shot?
No. Find the centre of the good shots and adjust for that. A single shot outside the group is left out.
When does Notch suggest a sight change?
Only when the group sits more than 3 mm off centre across a whole competition card.