Assuming 100y distance, that’s a reasonable approximation.At the risk of dumbing this down...a MOA scope has 1/4 inch clicks and a mil-dot scope has 1/3 inch clicks. Is that analogy close enough?
Assuming 100y distance, that’s a reasonable approximation.At the risk of dumbing this down...a MOA scope has 1/4 inch clicks and a mil-dot scope has 1/3 inch clicks. Is that analogy close enough?
This is the point I was trying to make. If you think in Metric then by all means go Mil.At the risk of dumbing this down...a MOA scope has 1/4 inch clicks and a mil-dot scope has 1/3 inch clicks. Is that analogy close enough?
I replied to Nate's PM and thought I'd share a perhaps better-written post here exploring the question: how fine do my turrets need to be?
The short answer is this: your turrets need to be fine enough to matter less than your variation as a shooter with a particular rifle and ammo.
Most shooters are familiar with SD as a measure of velocity variation, but we should mostly care about Standard Deviation as it pertains to ammo grouping relative to POA. I offer the simple idea here: if the scope turret adjustment is finer than the SD of your groups, then you are a larger contributor (on average) to shot group variation than your scope zero is.
Here's a quick test to know if you need turrets finer than 0.1 MIL clicks:
1. Shoot 20 rounds of your given ammo through the given rifle at a given POA.
2. Measure the radial distance from the POA to the outer edge of the 2nd worst shot. This gives you the size of the circle that fully contains 19/20 shots.
3. If this is less than twice the size if your scope click adjustment, you need finer turrets. In the case of a 0.1 Mil turret, you'd be putting 19/20 rounds inside a 0.72" circle (entirely within) at 100y.
Now, keep in mind, this 20 shot string is just one sample. For you to really, truly need finer scope turrets, you'd need to do this a few times and consistently best the 0.2 Mil barrier to need finer than 0.1 Mil turrets.
The justification behind the idea above is based on:
1) The assumption that group size is normally (Gaussian) distributed around the POA
2) The well-established idea that 2-sigma values (sigma= SD) correlate to 95% of a distribution
3) The idea that SD is the "average error" for a given shooter/ammo/rifle.
One criticism of this approach is the use of 95% confidence. This is pretty stringent and it means that you are pretty certain the scope here is holding you back.
You may elect instead to use a different confidence. And the group sizing and sample become proportionally much more accommodating to the lower standard. If you choose a 68% confidence (round it to 70%), then you'd only need to put 7/10 rounds inside a circle that is the size of the scope clicks.
Is it tougher to put 7/10 rounds inside 0.36" at 100y or to put 19/20 inside 0.72" at 100y? You be the judge. If you can do either one with consistency, then you might need turrets finer than 0.1 Mil.
You might not be surprised to learn that based on this logic, I will never need a turret finer than 0.1 Mil, and I suspect I'm not alone.
One question that occurred to me as I was thinking this through-- how do we ever really know the zero of our rifle?
Which of them is the "true" zero? Is is the center of the centers, like a meta-group?
What is the relationship between the confidence in our zero and the rifle's accuracy?
Finer scope adjustments make the problem worse, not better.
I'm willing to bet a lot of people with the really fine turrets end up chasing zeros a lot.
Basically using either 1/4MOA or 1/10th MIL at any distance the 1/4MOA is going to be the smaller unit of measurement if I understand it correctly.
Most shooters, & more important most spotters, don't think in terms of mil. My spotter tells me I'm 3 inches left of center, I can correct. If spotter tells me I'm 8 tenths of mil left, they get beat with a stick. No such thing as having a buddy, wife, kid, etc with binocs or regular spotting scope calling your shot, you still have to convert 3 inches to mil at whatever distance you're shooting. More power to the mil-mil crowd of they can do it. Reality is that most can not.
Most shooters, & more important most spotters, don't think in terms of mil. My spotter tells me I'm 3 inches left of center, I can correct. If spotter tells me I'm 8 tenths of mil left, they get beat with a stick. No such thing as having a buddy, wife, kid, etc with binocs or regular spotting scope calling your shot, you still have to convert 3 inches to mil at whatever distance you're shooting. More power to the mil-mil crowd of they can do it. Reality is that most can not.