Scope question using .25 clicks
- Thread starter tbeasley
- Start date
Yes, you are on the right track. Double the distance to the target - double the shift in point of impact, etc.
Two traps for young players to watch out for:
1. 1MOA actually equals 1.047" at 100yds, not 1.000". For most purposes, this is irrelevant and the 1MOA = 1" gives a realistic and usable approximation.
2. Scopes which have 1/4 MOA clicks or any other value don't always meet the advertised tolerances, some by a large enough margin to affect practical use.
So, if you wanted to shift your point of impact by 5" at 200yds, you'd expect it to be 10 x 0.25MOA clicks. Most times this will be right but it could also take 9 or 11 clicks, depending on how precisely the turret spindles are made.
Two traps for young players to watch out for:
1. 1MOA actually equals 1.047" at 100yds, not 1.000". For most purposes, this is irrelevant and the 1MOA = 1" gives a realistic and usable approximation.
2. Scopes which have 1/4 MOA clicks or any other value don't always meet the advertised tolerances, some by a large enough margin to affect practical use.
So, if you wanted to shift your point of impact by 5" at 200yds, you'd expect it to be 10 x 0.25MOA clicks. Most times this will be right but it could also take 9 or 11 clicks, depending on how precisely the turret spindles are made.
Forum Boss
Administrator
One other thing to note is that some scopes have a bit of a lash problem. I see this with the elevation knob on my Leupold LRT. To get an honest 1/4 MOA up, I go 3 clicks up, then two down. One click by itself sometimes just pulls the slop out of the system and you don't get a full 1/4 moa. I haven't seen this issue in Nightforces. FYI, as far as I know, at least with the LRT, the clicks are 1/4 moa, not 1/4".
Also, it is advisable with Leupold side-focus models to go back to the infinity stop before dialing out the parallax.
Also, it is advisable with Leupold side-focus models to go back to the infinity stop before dialing out the parallax.
BountyHunter
Gold $$ Contributor
Most scopes are really not what they advertise, only reasonably close.
Go to Dan Lilja's website and read his articles about testing scopes actual measurement across about 36inches to determine actual click value.
Many leupolds have problem with lash due to the small leaf spring in them. NF have spring tension pushing on the erector tube to prevent this. Cecil Tucker in TX does a conversion for Leupold scopes,similar to NF) to cure this also for $175. Second cure is say if you want to go up 3 click, then go up 8 and come down 5. This problem is most common with minor 1-3 click movement. By going past and then coming back down this normally prevents this from happening.
BH
Go to Dan Lilja's website and read his articles about testing scopes actual measurement across about 36inches to determine actual click value.
Many leupolds have problem with lash due to the small leaf spring in them. NF have spring tension pushing on the erector tube to prevent this. Cecil Tucker in TX does a conversion for Leupold scopes,similar to NF) to cure this also for $175. Second cure is say if you want to go up 3 click, then go up 8 and come down 5. This problem is most common with minor 1-3 click movement. By going past and then coming back down this normally prevents this from happening.
BH
BH, I agree with going past the required click number and then coming back to eliminate backlash.
What is often not stated though, is that you only need to do this in one direction. If you are making a clockwise adjustment,i.e. screwing the turret down), there is no need to overshoot because you are driving the erector lens assembly via the turret spindle so it has got to move.
On the other hand, if you are making a counter-clockwise adjustment, you are backing out the turret spindle and relying on the counter-pressure supplied by the springs to shift the erector lens assembly back against a hard stop on the end of the spindle. It doesn't pull it back, it just backs off the pressure and relies on the spring to shift it. If the workings are gummed up a bit or the springs are not up to the task, the erector lens might not shift and get bedded down against the stop until it gets a bit of a jolt.
So, I believe if you want to make a turret adjustment in a clockwise direction, move the required number of clicks and then stop. If you want to move counter-clockwise, go several clicks past it and then come at it from a clockwise direction.
In my experience and based on a my destructive internal examination of an old scope this practice will give the best consistency.
What is often not stated though, is that you only need to do this in one direction. If you are making a clockwise adjustment,i.e. screwing the turret down), there is no need to overshoot because you are driving the erector lens assembly via the turret spindle so it has got to move.
On the other hand, if you are making a counter-clockwise adjustment, you are backing out the turret spindle and relying on the counter-pressure supplied by the springs to shift the erector lens assembly back against a hard stop on the end of the spindle. It doesn't pull it back, it just backs off the pressure and relies on the spring to shift it. If the workings are gummed up a bit or the springs are not up to the task, the erector lens might not shift and get bedded down against the stop until it gets a bit of a jolt.
So, I believe if you want to make a turret adjustment in a clockwise direction, move the required number of clicks and then stop. If you want to move counter-clockwise, go several clicks past it and then come at it from a clockwise direction.
In my experience and based on a my destructive internal examination of an old scope this practice will give the best consistency.
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