Sighting in - confused

[yajsab]

you need good ballistic data to have any use of a ballistic app. should be good to a 1000 after a couple more shots.....

For discussion purpose based on the 3" high at 100 and 1" low at 200 impact, the only unknown variable is the speed.  With this data (assuming zero @ 200 yard), the calculator indicate a speed of ~2300 fps.  That's about 500 fps slower than what the box said (I understand it is 40 to 50 fps slower at 22" barrel).  Using the MOA rule, moving up 1" @ 200 will be 0.5" @ 100.  So with 3.5" high @ 100 and zero @ 200, the calculated speed is ~2200 fps.  Now it's roughly  600 fps slower than what the box said.

This is why I'm scratching my head on.

[pickardjw]

Can you post a picture of your targets? Bullet and BC used?

Ultimately, you're going to keep chasing your tail until you shoot a statistically significant amount of shots in each group.

Take the attached for another example of why you need to shoot more rounds in each group. If I ONLY used shots 1 & 2 (6 & 7) I'd say, "wow, I need to adjust my zero U1.25 MOA". In reality, those shots are towards the perimeter of the cone of fire and I only need to adjust U0.25 MOA. I'd be chasing that zero continuously and wondering why my ballistic solutions at further distances "aren't correct".

We don't know if your shots are in the center of the cone of fire or on the perimeter. Would also help to stop using linear units to describe angular measurements.

The limited data you have suggests a drop of 3.5 MOA between 100 and 200 yards. If your 100 yard shots are on the upper perimeter of the cone of fire and your 200 yard shots on the lower perimeter, the actual drop could only be 2.00 MOA, 1.75 MOA, 2.25 MOA, etc., which could be a correct ballistic solution.

[Clearcut]

I would if it was me with your situation verify your zero at 100… you said your shot groups at 100 and 200 were right and consistent so I would say that takes out scope movement.. I’d focus less on what your box said speed is. I have a chrono and while it’s gives me a very good starting point I still tend to reverse chrono or even tweak BC in a calculator to make my scope match what I see in paper…

[yajsab]

Here is a picture of the shots.

Don't pay attention to #7 but the elevation is consistent.  It was my bad.

[pickardjw]

Yeah, shoot two 5-10 shot groups. That target doesn't tell you anything useful.

[jstone]

Ammo? Maybe try different brands? I’m not an expert but my rifles love a certain brand