How to read groups
 

I have heard that there are ways of reading groups to know what to do to get tighter groups. Can some one give me the rules of thumb or a place to find info on this? Thank you Lee

RE: How to read groups
 

Vertical stringing is a sign of powder charge issues....need to increase charge most likely, but could possibly need to decrease. But, you may have missed a condition. Maybe a head wind switched and became a tail wind. Or It could be that the sand in your rest is bunched up and your gun isn't riding smoothly and evenly.


Horizontal stringing is a sign of missing a change in the conditions Ie wind, mirage.... But could possibly be a bedding issue, or an action screw loose.

Groups that group in two spots, Ie two groups a inch apart, indicates a bedding issues, or possibly a scope issue, or rapidly changing conditions.


Groups that where tight but suddenly go bad is an indicator that the scope mounts might be loosening. But, it also could be a barrel fouling issue, possibly the muzzle crown was damaged.

As you can see this isn't an exact science. There are multiple causes for each effect.