How does scope rail not aligned with barrel affect POI at different distances?

[mchees1]

I'll try to clarify my question and my reasoning. I have a rail mounted on top of the action. It appears to be aimed left of the barrel direction. So my thinking is that the scope direction and barrel direction are basically forming a V shape - the scope is aiming to the left leg of the V and the barrel is aiming to the right side of the V. I am wondering if when I zero at say 200m, does the V change to an X shape, where the point of impact only matches the point of aim at 200m. At other distances the barrel would be aimed to the right or left of where the scope crosshairs are looking. Or does zeroing the scope at 200m actually align the point of aim with POI at all distances? Does that 200m zero eliminate the problem of the rail not lining up with the barrel?

 

[243winxb]

Off Axis

 

[Ggmac]

my explanation was an exaggeration to show how even a little off center will change your poi . Granted .001 off will not be drastic enough to show up at 100 , but at ranges beyond 500 it will matter .

 

[Ggmac]

I'll try to clarify my question and my reasoning. I have a rail mounted on top of the action. It appears to be aimed left of the barrel direction. So my thinking is that the scope direction and barrel direction are basically forming a V shape - the scope is aiming to the left leg of the V and the barrel is aiming to the right side of the V. I am wondering if when I zero at say 200m, does the V change to an X shape, where the point of impact only matches the point of aim at 200m. At other distances the barrel would be aimed to the right or left of where the scope crosshairs are looking. Or does zeroing the scope at 200m actually align the point of aim with POI at all distances? Does that 200m zero eliminate the problem of the rail not lining up with the barrel?

Yes it will only be poi at the range you sight in BUT it will be statistically irrelevant due to the variables and average group size you can realistically shoot . In other words if you had it set up at 100 and shot a .5” group , it doesnt matter where it is ,just that you aim at the same spot , your group when shot with the scope not perfectly aligned, it will be within your average group size , GENERALLY.

 

[Full Chisel]

I'll try to clarify my question and my reasoning. I have a rail mounted on top of the action. It appears to be aimed left of the barrel direction. So my thinking is that the scope direction and barrel direction are basically forming a V shape - the scope is aiming to the left leg of the V and the barrel is aiming to the right side of the V. I am wondering if when I zero at say 200m, does the V change to an X shape, where the point of impact only matches the point of aim at 200m. At other distances the barrel would be aimed to the right or left of where the scope crosshairs are looking. Or does zeroing the scope at 200m actually align the point of aim with POI at all distances? Does that 200m zero eliminate the problem of the rail not lining up with the barrel

Scope can be both angled AND offset. If there is no offset, scope windage put everything on same line without any offset at ANY distance - the "V" will become a single line. But if the rail/scope has any offset, then the "V" will become an "X" as you put it. There is a good probability that any angle of rail comes with at least a tad of offset.
Go get a ruler and pencil and draw it out on paper. It will make more sense.

 

[jelenko]

Scope can be both angled AND offset. If there is no offset, scope windage put everything on same line without any offset at ANY distance - the "V" will become a single line. But if the rail/scope has any offset, then the "V" will become an "X" as you put it. There is a good probability that any angle of rail comes with at least a tad of offset.
Go get a ruler and pencil and draw it out on paper. It will make more sense.

^^^ This. End of discussion.

 

[mchees1]

Thanks for the help everyone.

 

[chop house]

Have you ever had two different loads with different point of impacts?

slightly off topic, but you have given me food for thought. i have a rifle that not only changes vertical point of impact with bullet weight and/or velocity but also changes horizontal... sometimes drastically.

i always thought it was bedding and set the rifle aside for later troubleshooting. now i wonder if it is barrel straightness or something....

 

[Full Chisel]

slightly off topic, but you have given me food for thought. i have a rifle that not only changes vertical point of impact with bullet weight and/or velocity but also changes horizontal... sometimes drastically.

i always thought it was bedding and set the rifle aside for later troubleshooting. now i wonder if it is barrel straightness or something....

I'd like to make a suggestion that you post your question as a separate post. It likely has little to do with scope or rail being misaligned as much as just the way the load and barrel behaves. You will probably get a lot of responses as it is an interesting and in depth discussion.