Brought across from a somewhat now stale hunting forum topic.
Just something to think about.
Consider this comparison between holdover and holdunder strategy.
I normally click to zero at the actual range using good scopes.
But often in open country I zero at a longer range and hold under.
Here is an example. I think one decimal is practically more than anyone can judge so we are rounding to one decimal of the inch.
For a rifle shooting 18 gr Exacts, BC 0.033, at 900 fps with a scope mounted 2 inches above the bore line. Note that the holdover / under is in inches at the target. If you know your target, be it a bird or animal, most of us know what an inch or two on its body/head looks like.
First examples for a 70 yard zero with holdunder/over; second row for 30 yd with holdover.
20, 30, 40, 50, 60, 70, 80, 90, 100 yards
- 1.2, -2.1, -2.5, - 2.3, -1.5, 0.0 @ 70 yd, +2.2, +5, +8.8 inches at target.
+0.2, +0.0, +0.4, +1.3, + 2.8, +5.0 @70 yd, +7.9, +11.5, +15.9 inches at target.
Note that holdunder from 20 to 80 yards for a 70 yd zero only varies from -2.5 at 40 yards to +2.2" (80 yd) inches at the target. So the pellet is within 2.5 inches of zero aim (70 yd) from muzzle to 80 yards.
But for a 30 yd zero the holdover varies from 0" (30 yd) to +7.9" (80 yd).
I don't have any scopes with mildots or hash marks ( that is not a judgement on their usefulness ) but out to 80 yards I have little trouble at guessing to a couple of inches against the head or body of a rabbit or known bird.
# Note that 2 inches of scope height above bore is a very useful amount. Going even higher can flatten the apparent trajectory even more at the longer ranges.
Regards to all, Harry.
Just something to think about.
Consider this comparison between holdover and holdunder strategy.
I normally click to zero at the actual range using good scopes.
But often in open country I zero at a longer range and hold under.
Here is an example. I think one decimal is practically more than anyone can judge so we are rounding to one decimal of the inch.
For a rifle shooting 18 gr Exacts, BC 0.033, at 900 fps with a scope mounted 2 inches above the bore line. Note that the holdover / under is in inches at the target. If you know your target, be it a bird or animal, most of us know what an inch or two on its body/head looks like.
First examples for a 70 yard zero with holdunder/over; second row for 30 yd with holdover.
20, 30, 40, 50, 60, 70, 80, 90, 100 yards
- 1.2, -2.1, -2.5, - 2.3, -1.5, 0.0 @ 70 yd, +2.2, +5, +8.8 inches at target.
+0.2, +0.0, +0.4, +1.3, + 2.8, +5.0 @70 yd, +7.9, +11.5, +15.9 inches at target.
Note that holdunder from 20 to 80 yards for a 70 yd zero only varies from -2.5 at 40 yards to +2.2" (80 yd) inches at the target. So the pellet is within 2.5 inches of zero aim (70 yd) from muzzle to 80 yards.
But for a 30 yd zero the holdover varies from 0" (30 yd) to +7.9" (80 yd).
I don't have any scopes with mildots or hash marks ( that is not a judgement on their usefulness ) but out to 80 yards I have little trouble at guessing to a couple of inches against the head or body of a rabbit or known bird.
# Note that 2 inches of scope height above bore is a very useful amount. Going even higher can flatten the apparent trajectory even more at the longer ranges.
Regards to all, Harry.
