Zeroed at 100 but shouts 4” high at 200

[Varmint Hunter]

I would wonder if your 100 yard hit is the "first zero" shown in the picture below, not the second. Usually the bullet crosses your line of sight around 50 yards out for the "first zero."

If you check your point of impact at 25 and 50 yards it might tell you.

That was my first thought - but then I was wondering if it was even possible.

 

[K.E.C. Darkside]

Are you using factory ammo or reloads.
And what weight bullets are you using.
Have you tried just shooting to 200 with a cold bore..and see what it does.
Barrel contour and length, maybe your barrel getting to hot.
Hope this helps.

 

[tbroz]

I've shot both factory loads and reloads. 250 and 300. The barrel was cold at 200. I waited for the other guys to finish before moving to 200. About 15 min to 20. Its a 26" barrel

 

[bluedog69]

How big is your 200 yard group?
Sight it dead on at 200. Then check it at 100.

 

[Dr. Vette]

That was my first thought - but then I was wondering if it was even possible.

Yes

 

[8andbait]

Ok, so just so we are all on the same page…
You shoot at 100 and it's perfect zero.
Then you don't change anything, shoot at 200 and it's 4" high?
Then you go back to 100 and it's perfect zero again?

 

[lancetkenyon]

I would dial the scope down 4 MOA (to lower the point of impact) and shoot a 100 again and see where the point of impact is.
What scope are you running ?

No. @ 200 yards, dialing down 4 MOA is an 8" correction. You would dial 2MOA for a 4" correction @ 200 yards.

1 MOA @ 100 yards is 1.047".
1 MOA @ 200 yards is 2.094".
1 MOA @ 400 is 4.188".

 

[lancetkenyon]

I would wonder if your 100 yard hit is the "first zero" shown in the picture below, not the second. Usually the bullet crosses your line of sight around 50 yards out for the "first zero."

If you check your point of impact at 25 and 50 yards it might tell you.

No.

100 yard zero is crossing the highest point of flight in the apex and line of sight. You should have a low POI before 100 yards, and after 100 yard (actually probably pretty flat from 90-110 yards). Anything beyond 110 should start to drop off again.

If you have a 200 yard zero, your graph shows true bullet flight. You should cross somewhere around the 50 yard distance, highet POI at apex of flight would be around 130 yards, and then drop back off to 200 yards, crossing line of sight again. Falling off after 200.

 

[captrjc]

No. @ 200 yards, dialing down 4 MOA is an 8" correction. You would dial 2MOA for a 4" correction @ 200 yards.

Yea, I'm aware of the math, It was simply to make a drastic change in the scope to see what it tracked at. I didn't suggest it to rezero it.

 

[cajun]

How many shots to confirm your zero?
You can also do a box test and check the tracking. Personally I would not put much faith in a 10 yo Bushnell. Do you have another scope you can try?

 

[captrjc]

If you have a 200 yard zero, your graph shows true bullet flight. You should cross somewhere around the 50 yard distance, highet POI at apex of flight would be around 130 yards, and then drop back off to 200 yards, crossing line of sight again. Falling off after 200.

My Lapua with 300 gr bergers is zeroed at 200 yds, at 38 yds it shoots right at point of aim.

 

[tbroz]

Ok, so just so we are all on the same page…
You shoot at 100 and it's perfect zero.
Then you don't change anything, shoot at 200 and it's 4" high?
Then you go back to 100 and it's perfect zero again?

Yes you are correct

 

[Maol]

His 100 yard zero is the first zero.

 

[tbroz]

How many shots to confirm your zero?
You can also do a box test and check the tracking. Personally I would not put much faith in a 10 yo Bushnell. Do you have another scope you can try?

At least 10 rounds with three different rounds. I'm waiting on the new scope to come.