Why does a load shoot two separate goups??

[FishDFly]

I have read and found by personal experience that wetter/tighter patches shoot higher. Looser/dryer patches shoot lower.

Atmospheric pressure changes can cause groups to shift up and down. High pressure causes groups to go up and low pressure causes groups to shift down.

Need to take a hydrometer with you to the range and watch it carefully between shots.

Grouping right and left is caused by the deviation from shooting right or left of true north. Need to take a compass with you and adjust your target so it faces exactly true north to get your shots centered on the target..

 

[Grenadier1758]

While @FishDFly's suggestions won't stand up to critical thinking, some of the other suggestions may gave some merit.

Lead, being non magnetic is not effected by the earth's magnetic field.

Air pressure changes far too slowly to justify needing a barometer to read and make sighting adjustments.

Relative humidity may be responsible for fouling build up, but fouling in the bore can be mitigated by loading procedures. The dampness of the patch will have more effect than relative atmospheric pressure.

@Steel Guitar, you need to ensure all the conditions for each shot are consistent. This means all the components, powder charge, propellant, projectile, lubricant, sight picture and hold. Avoid prelubricated patches.

Do you have cataracts? Floaters?
Do you have minor issues seeing the sights?
Have you put a diopter (peep hole) on your shooting glasses to improve the sight picture?

 

[Salty]

Yeah I probably got it backwards or upside-down. Sometimes it happens with me

I kept confusing it also. The way it was explained to me is that a wet patch is tighter and thus prevents gases from escaping around the ball. More push on the ball. Higher trajectory.

 

[Steel Guitar]

Thanks again for all of your help guys! I learned a lot. I've had catarack surgery on both 15 years ago and see better.

 

[waksupi]

Ya know, if you are using pillow ticking, and don't line the stripes up directly at the center of the target, your shots will go the direction of the stripes!

 

[Grenadier1758]

I use #40 cotton drill cloth. There's no stripes to align with the target.