POI Question

YZ-80

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Feb 20, 2019
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Location
Maryland
Guys, I’m between shot groups letting my barrel cool. I’m working on that ELD-M ladder with the .308 with my 43.5 and a 44.0 (Varget) rungs of the ladder left. Groups are fantastic but POI is going down with increasing charge weight. This is the oppiset of what I typically see. Testing @ 100 yards and it’s around 40 degrees w/ high humidity but very calm. What gives? I feel like I should know this.
 

Hespco

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Mar 6, 2019
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W. Montana
As velocity increases the bullet exists the barrel sooner as the barrel lifts under recoil striking lower on the target.. A slower bullet exists the barrel higher up on the recoil arc striking higher on the target.. This is typical & normal. When you reach your desire load you will adjust your scope accordingly for your proper sight in elevation. No problem here.
 

Capt RB

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Dec 1, 2014
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The whip in the barrel is releasing the bullet after it has started down in its oscillation. If you are checking your velocity it should show that the velocity over that span of charges is close to the same signifying you are in the harmonic node the rifle wants to shoot that combination of powder pressure vessel(brass volume) bullet and primer. What are the velocities around that phenomenon
 

YZ-80

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Joined
Feb 20, 2019
Messages
1,235
Location
Maryland
As velocity increases the bullet exists the barrel sooner as the barrel lifts under recoil striking lower on the target.. A slower bullet exists the barrel higher up on the recoil arc striking higher on the target.. This is typical & normal. When you reach your desire load you will adjust your scope accordingly for your proper sight in elevation. No problem here.
That explains it. I don’t understand why I’ve never noticed it. Maybe it’s more pronounced with heavier bullets?
 
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