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I have read a lot about zeroing my scope and in many explanations 100 yards is used as a example distance to zero a rifle scope. And in several discussions/ videos a drawing of the line of site of the scope intersecting with the 'highest' point in the bullet's trajectory at 100 yards (the zero distance) seems to me to be one of two scenarios. Isn't it possible (second scenario) that the line of site of the scope (if gun is stationary and reticle lowered more) could intersect the bullet's trajectory at two points ( A and B)? 'A' being a point along the bullet's ascent (before reaching its highest point along trajectory) and 'B' being a point along the bullet's descent? If so, in the first scenario, the gun would be zeroed at 100 yards, but in the second scenario it would be zeroed at a distance less than 100 yards and another distance farther than 100 yards. Am I understanding things wrong or am I presenting a valid point? If I'm correct, then the rule that a gun will always shoot 'low' if aimed at a target closer or further than the point of zero (100 yards in many explanations) would not always be true (if the second scenario applies). Right? Any advice would be appreciated.
 

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This might help you understand the mechanics of what's going on.

https://blog.cheaperthandirt.com/exterior-ballistics/

In the illustration, the bullet crosses the scopes line of sight around 30-35 yards based on the illustration or so and then comes down at 100. Obviously this would be slightly different for each round.

Personally I've never bothered analyzing the exact distance of the up or down on POI on my center fire rifles for two reasons, 1) the difference is relatively small (around 2") or less and I generally shoot at distances well in excess of 100 yds unless I'm doing load development.

Now if you are looking at shooting a .22LR then you might consider zeroing at 50yds and note your POI's at 10yd increments out to 50 if you want to get squirrels with head shots.
 

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This might help you understand the mechanics of what's going on.

https://blog.cheaperthandirt.com/exterior-ballistics/

In the illustration, the bullet crosses the scopes line of sight around 30-35 yards based on the illustration or so and then comes down at 100. Obviously this would be slightly different for each round.

Personally I've never bothered analyzing the exact distance of the up or down on POI on my center fire rifles for two reasons, 1) the difference is relatively small (around 2") or less and I generally shoot at distances well in excess of 100 yds unless I'm doing load development.

Now if you are looking at shooting a .22LR then you might consider zeroing at 50yds and note your POI's at 10yd increments out to 50 if you want to get squirrels with head shots.
+1
 

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In the illustration, the bullet crosses the scopes line of sight around 30-35 yards based on the illustration or so and then comes down at 100. Obviously this would be slightly different for each round.
 

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In the illustration, the bullet crosses the scopes line of sight around 30-35 yards based on the illustration or so and then comes down at 100. Obviously this would be slightly different for each round.
Is there a question there?
 

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What you are talking about is that a bullets flight is actually a parabola or curve rather than a line. In the scenario you present a bullet could at some point rise over the POI and then come back down below it crossing it again. The problem with your 'question?' is you have to consider acceleration due to gravity which is about 9.8 meters per second. What this means is most cartridges - rifle at least will pass the 100 yards before gravity has had enough time to act on the bullet enough to pull it back down past the POI. If you move to 300 yards this will start to become a visible thing. A 'zero' on a scope does not mean the highest point the bullet reaches when leaving the muzzle. It is the POI at the given range you have sited in for. You can zero at 100 yards, 300 yards, etc. Assuming your scope is exactly horizontal to the earth bullets do not 'rise' coming out of a barrel. Not sure where you got that from. If you zero at 300 the gun will be shooting slightly upward so that as the bullet drops it hits its mark. BTW - a lot of boxes of factory ammunition have the drop on the box but remember this is based on a certain barrel length. Just site in until you hit the 100 bull and be done with it.
 

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Hi guys ,I have a different problem. I put on rifle -20MOA Spuhr mount and my scope Kahles 1050,after zeroing (I had to go 20MOA up) I have aprox.40MOA range to go up. Basically I lost 20 MOA from Up. Of course mount is attached in correct way. Apologize in advance for stupid question
 

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Hi guys ,I have a different problem. I put on rifle -20MOA Spuhr mount and my scope Kahles 1050,after zeroing (I had to go 20MOA up) I have aprox.40MOA range to go up. Basically I lost 20 MOA from Up. Of course mount is attached in correct way. Apologize in advance for stupid question
Your mount is on backwards if you used to have 60 MOA available.
 

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The 1050 has 55MOA of total travel for elevation.... 27.5MOA above and below optical center. In a perfect world adding a mount with 20MOA of verticle tilt would give you 47.5MOA of verticle adjustment from your new zero. We seldom live in a perfect world, remember 1MOA is only 0.0167 degrees.... lots of things can contribute to errors... unevenly tightened rings, mount to rail bolts not torqued properly, etc. I don't know what you are shooting but your 40MOA of available elevation from your zero is more than enough to get you to 1000yd with a quality match round. Have fun and shoot as often as you can.

Cheers,
Don

Hi guys ,I have a different problem. I put on rifle -20MOA Spuhr mount and my scope Kahles 1050,after zeroing (I had to go 20MOA up) I have aprox.40MOA range to go up. Basically I lost 20 MOA from Up. Of course mount is attached in correct way. Apologize in advance for stupid question
 
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