Your Groups Are Too Small

Harvey_NW

WKR
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Sort of- what MR won’t do is tell you what size target the system will hit. Or, it won’t do it without charts, and Excel sheets, math, and general time wasters. Using mean radius (as well as large shot group ES) makes sense from a large scale testing and contract process. It does not make sense in the “I need to see if this combo will hit what I need to hit, and zero correctly” process.

Hitting living things isn’t about “average distance from center”, it’s about “worst” shot from center.
Isn't MR fairly linear to dispersion when the groups stabilize?
 

Formidilosus

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Shoot2HuntU
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To be clear, all the shooting I did to inform the video was with a 22, not a big deal. Most of the rest of what I'm talking about is in interpreting the data. As far as what I've "wasted" on the 284, I think the main point of contention is the 25rds or so for the powder sweep? We agree that testing different components is worthwhile. Your method consumes 20rds to do this, if I skip the powder sweep and just find pressure and back off a grain (10rds) then proceed to validation (as much as you want, the more the better), I think my method essentially collapses to yours. Remember, the first sweep of testing I described was all different component combos.

The last 12-15 rifles it has been 20-24 rounds to “find” a load, be zeroed, and trued up to max terminal range. I’m not into ballistic masterbation.



Regarding 1.2MOA, let’s be clear about what metric that relates to again - 20 shots.


I’m aware, and I also stated that precision is just fine.


Also, it's 1.5MOA informed by 51 shots. Do you have a 51 shot group for any of your guns? You know what your 20-30 shot group ES is (roughly 2 sigma level),

51 rounds? No. I have 30, 50, 100, 200, and 250 round groups. Though most of those aren’t from bolt actions.


but without insight on the distribution of shots inside that group, how do you know what your true worst case over the life of the rifle will be?

Because the probability of 20’ish shot extreme spread brings the error way inside of what effects hit rates. Your load difference of .28moa (1.5 to 1.78moa) has about zero functional effect on hit rates on game animals in the field. It’s totally swallowed up in errors that you can’t account for. 5 minutes of dry fire will do more for increasing hit rates than 5 minutes spent measuring the SD of rounds in a group. It’s functionally meaningless.
 

solarshooter

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Isn't MR fairly linear to dispersion when the groups stabilize?
Mean radius on it's own isn't useful without standard deviation. If you assume groups are normally distributed, you can make some assumptions. But you'd have to track many groups, and we get back to essentially the same data collection exercise.
 

Formidilosus

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Shoot2HuntU
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Isn't MR fairly linear to dispersion when the groups stabilize?

Yes’ish with enough shots fired. So I have a gun that averages .39” mean radius- what size target will the gun legitimately be expected to hit?
 

Formidilosus

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Shoot2HuntU
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What inputs for rifle precision does WEZ use?


For precision, extreme spread. Really based around a 30 shot ES.



The way I see it, I spend a couple hours loading, a couple hours driving and shooting, and I can spare 10-15 mins to input data on a spreadsheet when I'm done.

Yes. And please take this in good spirit- you’re an engineer- you want to “engineer” on everything even if it is a time waster and gets you nowhere that other methods would get you in less time, money, effort.
 

solarshooter

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Because the probability of 20’ish shot extreme spread brings the error way inside of what effects hit rates. Your load difference of .28moa (1.5 to 1.78moa) has about zero functional effect on hit rates on game animals in the field. It’s totally swallowed up in errors that you can’t account for. 5 minutes of dry fire will do more for increasing hit rates than 5 minutes spent measuring the SD of rounds in a group. It’s functionally meaningless.
So does your 24 rounds include a 20rd group?

Agreed, other errors, especially wind, dominate the equation. I still don't see it as such a zero sum game, where time spent doing load dev decreases time practicing at long range or from positions. It might for someone who can easily shoot long range, and is actually making a choice between doing load dev and shooting in the wind. But even still, we're talking about a difference of a 25rd powder sweep * x combinations, call it 100 out of 1500ish rounds in my shooting year. Seems a small cost for optimizing the gun.
 

Formidilosus

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So does your 24 rounds include a 20rd group?


Nope. Because it isn’t necessary usually. If 10 rounds are under 1.5 MOA at 100y, and the next ten at 900-1,100 yards are also around 1.5 MOA- precision of the rifle isn’t the reason someone is going to miss a deer’s chest at realistic ranges. If those first ten round go over 1.5 MOA, change bullets or powder.


Agreed, other errors, especially wind, dominate the equation. I still don't see it as such a zero sum game, where time spent doing load dev decreases time practicing at long range or from positions. It might for someone who can easily shoot long range, and is actually making a choice between doing load dev and shooting in the wind. But even still, we're talking about a difference of a 25rd powder sweep * x combinations, call it 100 out of 1500ish rounds in my shooting year. Seems a small cost for optimizing the gun.

But you haven’t “optimized” anything. 1.2-1.5 MOA for 20 rounds can and is had on demand from factory ammo in factory guns.
 
Joined
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Yes’ish with enough shots fired. So I have a gun that averages .39” mean radius- what size target will the gun legitimately be expected to hit?
I’m guessing your question is rhetorical but..

You could calculate an R95, 2.1 x 0.39 x 2= 1.63”

So theoretically 95% of the shots should fall within 1.63 moa

Honestly I only look at mean radius it because it’s an option on ballistic X.. personally I just shoot a 10-20 shot group.
 
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@solarshooter , you could just do an open-ended search on posts by Formidilosus and decide for yourself, but I'll save you a little bit of time and let you know that you are always wrong. Always. If you don't agree, most of the time, others will jump in and tell you you are wrong. I think those that used to disagree no longer post much in this forum anymore.
 

solarshooter

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But you haven’t “optimized” anything. 1.2-1.5 MOA for 20 rounds can and is had on demand from factory ammo in factory guns.
At the very least, I've picked a more accurate combo of components. And no one makes 284 ammo, but that's a problem of my own creation by picking somewhat of a niche cartridge. I still think this is not much worse than buying 4 different types of box ammo and testing them. Probably cheaper considering cost per rd is lower. And we haven't even touched on MV consistency, which I think can be much better in hand loaded ammo. Yes yes MV induced error is not a big deal on deer sized targets compared to other sources of error. But how many of these small errors do you have to stack for them to begin making a noticeable difference? Going from 50 to 60% hit rate might only be a 10% increase, but it's a 20% improvement.
 
Joined
Dec 4, 2018
Messages
2,501
Sort of- what MR won’t do is tell you what size target the system will hit. Or, it won’t do it without charts, and Excel sheets, math, and general time wasters. Using mean radius (as well as large shot group ES) makes sense from a large scale testing and contract process. It does not make sense in the “I need to see if this combo will hit what I need to hit, and zero correctly” process.

Hitting living things isn’t about “average distance from center”, it’s about “worst” shot from center.
As far as hitting living things in real world conditions…I’m not at a level where my weapons precision really matters that much. Wind and shitty fundamentals are what I’m working on personally. Probably will learn more from my 1.8moa .223 than I will from my 1MOA 25 creedmoor or 22 creedmoor.

The math and wallet groups are because shooting it fun and I can’t shoot in the mountains every day 😬
 
Joined
Dec 4, 2018
Messages
2,501
At the very least, I've picked a more accurate combo of components. And no one makes 284 ammo, but that's a problem of my own creation by picking somewhat of a niche cartridge. I still think this is not much worse than buying 4 different types of box ammo and testing them. Probably cheaper considering cost per rd is lower. And we haven't even touched on MV consistency, which I think can be much better in hand loaded ammo. Yes yes MV induced error is not a big deal on deer sized targets compared to other sources of error. But how many of these small errors do you have to stack for them to begin making a noticeable difference? Going from 50 to 60% hit rate might only be a 10% increase, but it's a 20% improvement.
I don’t think you’re wrong and what you are discussing is interesting. I think what some guys are getting at, is when it comes to killing animals your analysis is probably overkill and you could arrive at the same conclusion, faster. But hey there is nothing wrong with arriving at conclusions based on your own data set and experimenting. What a lot of guys have realized is that the experimenting that matters most for hunting, happens from field positions in the wind, not so much at the reloading bench.
 

huntnful

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Oct 10, 2020
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To be clear, all the shooting I did to inform the video was with a 22, not a big deal. Most of the rest of what I'm talking about is in interpreting the data. As far as what I've "wasted" on the 284, I think the main point of contention is the 25rds or so for the powder sweep? We agree that testing different components is worthwhile. Your method consumes 20rds to do this, if I skip the powder sweep and just find pressure and back off a grain (10rds) then proceed to validation (as much as you want, the more the better), I think my method essentially collapses to yours. Remember, the first sweep of testing I described was all different component combos.

Regarding 1.2MOA, lets be clear about what metric that relates to again - 20 shots. I think that's actually pretty good, and I would love to see other people post their 20 shot groups so I could know where I stand. Also, it's 1.5MOA informed by 51 shots. Do you have a 51 shot group for any of your guns? You know what your 20-30 shot group ES is (roughly 2 sigma level), but without insight on the distribution of shots inside that group, how do you know what your true worst case over the life of the rifle will be?
I think he has pictures of a couple hundred round groups lol.

He’s not belittling your 1.2 MOA group. I think he’s saying that that’s pretty average for any hunting system with proper components and extra work to achieve that size group isn’t really necessary. And all you really need to kill stuff out to a very long ways anyway.

Here’s a 1.1 MOA 15 round group just fire forming brass for a wildcat. Bullets stuffed into the lands with some podunk random powder. I promise if you use a good steel action, bedded into a good stock, with a good steel barrel, almost everything shoots 10-20 shots under 1 MOA pretty easily.

IMG_0384.jpeg
 
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