Who goes with the load that groups at distance and pays zero attention to what the magneto says? I see tons of 100 yard groups and lots of magneto numbers posted but not a lot of groups at extended ranges.
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Does es and sd really matter?
- Thread starter PAYDIRT
- Start date
i pay attention to all of it
I believe the bullet. On paper, preferably 100 for zero, 200, 300, 500, 600 for actual DOPE with solid DA info to dial in ballistic guesstimator.
I’ve had loads that were pretty ugly across an Oehler that were solid half moa shooters.
That said, in the absence of ability to check paper at distance, a slim ES should be better as you reach out at distance.
I’ve had loads that were pretty ugly across an Oehler that were solid half moa shooters.
That said, in the absence of ability to check paper at distance, a slim ES should be better as you reach out at distance.
IF it groups well at distance with little vertical stringing, then the velocities must be within a reasonable range. ES means almost nothing, except as a reason to try another load because it's too high. If you are shooting at 1K, an ES of 60fps is going to end up being a problem, so move on.
Steel’s fun, paper’s an evil bitch that isn’t there to stoke your ego-but never lies.
If you read over on the accurate shooter forum the top 1000yard bench rest shooters they shoot and go with only what the paper shows at 1000 yards. I have seen them mention more than once that the smallest groups (less than 2inches) sometimes have an ES over 20 which they do not care about as the paper never lies.
In saying that average joe shooting .5 - 1moa off a bipod and rear bag doesn't really have a hope in hell in being able to determine any of this precisely enough at 1000 whether its ES or something else affecting groups. The .1moa bench rest guns really show the truth.
In saying that average joe shooting .5 - 1moa off a bipod and rear bag doesn't really have a hope in hell in being able to determine any of this precisely enough at 1000 whether its ES or something else affecting groups. The .1moa bench rest guns really show the truth.
I go off of my groups at distance , just surprised at how much attention everyone pays to a chrono and groups @100.
Look at the groupings at distance. Forget the ED/SD measurements. If your repeated load at distance groups, what does the ED/SD measurement matter? A 1 inch 5 shot group at 300 yards is more than enough to win any PRS style match. Or kill any animal with in ethical hunting distances. Extreme shooting disciples call for crazy load development. Casual shooting, PRS, local matches and the like are not extreme shooting disciples. Bench rest, extreme Long range are and the like are. Shoot more, develop less. Hope this helps.
I don't even own a chrono and don't do ladder or ocw tests. I only go off of how it groups at distance. Just trying to figure out why so many pics of 100 yard groups and chrono numbers we see.
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Great than your on the right path! I would highly suggest ladder test. Finding the velocity node really speeds up load development. The reason for the group and ED/SD measurements are to justify purchase of the Chronograph. I've posted about this before. But it begs repeating.
For hunting, causal shooting, PRS, and the like keep it simple.
Do load development in the hottest weather you would shoot in.
Ladder test with at least two strings to cover shooter induced flyers.
Find the top node, split the difference and play with seating depth.
IF your not running max pressures, you should not have an issue with seating depth changing pressures drastically. You will also fine its not likely for fall out of the node if not running max pressures.
Do your grouping for the load at distance. 200 for windy days, 300 for calm days.
Once that's settled guess at you velocity and plug it into your calculator. Zero at 100. Check drop at distance. Then correct for difference. There is you velocity. no need for a chronograph.
I do all my load development in 110 temps. Here in the Lone Star State it gets hot. Many a time I have watched people blow primers and stick bolts closed not accounting for our heat. When running max pressures, they also have to redevelop their load for the winter. Temperature stable powder is very important down here for the year long shooter. It's worth it to me to give up so velocity for predictable and reliable performance. Not trying to step on toes, just trying to help.
For hunting, causal shooting, PRS, and the like keep it simple.
Do load development in the hottest weather you would shoot in.
Ladder test with at least two strings to cover shooter induced flyers.
Find the top node, split the difference and play with seating depth.
IF your not running max pressures, you should not have an issue with seating depth changing pressures drastically. You will also fine its not likely for fall out of the node if not running max pressures.
Do your grouping for the load at distance. 200 for windy days, 300 for calm days.
Once that's settled guess at you velocity and plug it into your calculator. Zero at 100. Check drop at distance. Then correct for difference. There is you velocity. no need for a chronograph.
I do all my load development in 110 temps. Here in the Lone Star State it gets hot. Many a time I have watched people blow primers and stick bolts closed not accounting for our heat. When running max pressures, they also have to redevelop their load for the winter. Temperature stable powder is very important down here for the year long shooter. It's worth it to me to give up so velocity for predictable and reliable performance. Not trying to step on toes, just trying to help.
Well, for me, I do a load development run just to find that one load with the best numbers and the smallest group at 100. It's probably not going to be the fastest load because I don't want to have issues in the 100+ degree desert during the summer. Then I load the shit out of it and have fun. I'm not an F class or benchrest guy, so the "ding" is the name of the game for me.
I may do a 700 or 1000 paper competition in a few months just to see where I'm at.
I may do a 700 or 1000 paper competition in a few months just to see where I'm at.
wind is a big variable for group size. plug in 5 and 7mph in your calculator
and so is sd/es. plug in 2790 and 2810. then do 2780 and 2820.
there's a reason you see a lot at 100/200/300 and not as much groups at distance. your ES/SD isnt gonna change as you go further out but more is going to impact it. if you can shoot good, a .5MOA gun at 100 will continue that....IF you can read the changes. otherwise the groups will open up and it very well may not be the loads fault
and so is sd/es. plug in 2790 and 2810. then do 2780 and 2820.
there's a reason you see a lot at 100/200/300 and not as much groups at distance. your ES/SD isnt gonna change as you go further out but more is going to impact it. if you can shoot good, a .5MOA gun at 100 will continue that....IF you can read the changes. otherwise the groups will open up and it very well may not be the loads fault
i do load workup at 100 yds and get ragged holes, then chrono
100 yds is 20 min from my house...distance is 1+ hrs and none of the ranges have paper set up at distance
if its sub 1/2 moa day in, day out @ 100, and low ES/SD...it takes care of what happens down range
ive shot against a lot of people who do load work at distance even when it came to group size at distance competitions...nothin has made me feel the need to change
100 yds is 20 min from my house...distance is 1+ hrs and none of the ranges have paper set up at distance
if its sub 1/2 moa day in, day out @ 100, and low ES/SD...it takes care of what happens down range
ive shot against a lot of people who do load work at distance even when it came to group size at distance competitions...nothin has made me feel the need to change
I think logistics is the main reason.
I do not have the ability to shoot paper beyond 100 yards. All the ranges I can shoot at have steel beyond that, but do not allow for shooters to go downrange for paper targets.
If they did have that ability, everyone else shooting steel would be quite annoyed at the guy wanting to go cold all the time to put up and check targets.
So I rely on 100 yard groups and chrono. Occasionally I’ll try to shoot a group on steel st distance but that’s difficult to tell at times.
I do not have the ability to shoot paper beyond 100 yards. All the ranges I can shoot at have steel beyond that, but do not allow for shooters to go downrange for paper targets.
If they did have that ability, everyone else shooting steel would be quite annoyed at the guy wanting to go cold all the time to put up and check targets.
So I rely on 100 yard groups and chrono. Occasionally I’ll try to shoot a group on steel st distance but that’s difficult to tell at times.
Won’t bother posting all the environmentals but 140eldm going 2700 and 2740 has a .3mil difference at 1k.
Linearly, thats 10.8”.
So yea, ES matters.
Linearly, thats 10.8”.
So yea, ES matters.
True, but when one bullet impacts and the next one misses low at distance, and your chrono tells you that you had a 20 or more ES.......you can’t use the truth of the bullet to make a correction.
You have to hope the next round doesn’t suffer from the same ES as the last.
Case in point. You shoot a 5rnd group at distance and it groups well. You were a victim of mathematical variance and the 5 you shot were all pretty well and close.
You didn’t bother with chrono. If you had, and chrono’d over a larger sample, you’d have seen your ES was 20
You’re at a match and there is a 10” square plate.
Your gun is a 1/2 moa gun. So, your gun is good 5.235”.
Now, with your SD, you’ve added .1mil into the equation. So another 3.6”
You now have an 8.835” or an .84moa gun shooting at a 10” plate. Sometimes it’s a .5moa and sometimes it’s a .84moa.
Oh and you only get 2 shots at this plate.
You didn’t bother with chrono. If you had, and chrono’d over a larger sample, you’d have seen your ES was 20
You’re at a match and there is a 10” square plate.
Your gun is a 1/2 moa gun. So, your gun is good 5.235”.
Now, with your SD, you’ve added .1mil into the equation. So another 3.6”
You now have an 8.835” or an .84moa gun shooting at a 10” plate. Sometimes it’s a .5moa and sometimes it’s a .84moa.
Oh and you only get 2 shots at this plate.
I’m sure my math is off somewhere. Substitute any numbers you need. Point is, it all goes hand in hand.
Chrono tells you the consistency of your loads.
Bullet tells you what real world is doing to the bullet in flight.
Chrono tells you the consistency of your loads.
Bullet tells you what real world is doing to the bullet in flight.
Acceptable depends on the range and target size. If you use the AB Weapon Employment Zone or Coldbore Hit Threshold functions you can see what a given velocity variation does to your group. ES in and of itself is not a valuable number, SD is the only really important number and teh sample size needs to be big enough to give a high confidence that the number is valid. 20 rounds is a reasonable sample size for 90%+ confidence, note that they rounds must be fired under controlled conditions, temperature of the gun and ammo should not vary more that a few degrees.
It is desirable to get single digit SD's, but not required if the target is large enough or the range is short enough. For example, if you are shooting deer, presume an 8" circle as the vital zone and a max range of 400 yards then an SD of even 20 should not pose a problem. If you are shooting a 36" square at 2500 yards, an SD of 12 is pretty much a disaster.
It is desirable to get single digit SD's, but not required if the target is large enough or the range is short enough. For example, if you are shooting deer, presume an 8" circle as the vital zone and a max range of 400 yards then an SD of even 20 should not pose a problem. If you are shooting a 36" square at 2500 yards, an SD of 12 is pretty much a disaster.
Adding SD to chrono readouts was the work of a cruel, evil genius.
Extremely subtle, but inhumanly evil.
I have yet to hear a shooter describe a legitimate use for it that is also legitimate statistically.
Extremely subtle, but inhumanly evil.
I have yet to hear a shooter describe a legitimate use for it that is also legitimate statistically.
SD does matter because it tells you what you might expect with some amount of certainty. But, it doesn't matter because almost no one shoots enough to make it statistically relavent. 5 shots is the absolute minimum that can give you an 80% confidence interval, but that doesn't make it statistically relavent.
ES does matter because it tells you about the consistency of what you have shot. But, it doesn't matter because it doesn't tell you anything about what you are about to shoot.
Did your bullet impact the target, where it was expected? That is what really matters.
ES does matter because it tells you about the consistency of what you have shot. But, it doesn't matter because it doesn't tell you anything about what you are about to shoot.
Did your bullet impact the target, where it was expected? That is what really matters.
Not sure how you answer the last one without the first two. Your use of real statistics is pretty flawed here
I'd suggest a class in statistics then. Perhaps this article would be of some use.
Chronograph Statistics
It should seem obvious that ES is hardly relevant, and SD is clearly the important number. If you want to know something about a population, a larger sample is better that a smaller sample. No matter the size of the population, ES considers two data points. If you want to know what the mean velocity of the next 1000 rounds will be and what the probable min/max spread will be, you'll need to shoot at least 20 and preferably 40 rounds through the chronograph.
That being said, velocity is only one part of the picture. You could actually have a load with a very low SD that just does not group well. If your SD is very large though, you are not going to get good consistent groups at distance.
I get it shooting as tight and as stable as I can at 100. This means finding a tight load, and then shooting the same load again to verify consistency. 4 shot groups at a minimum. Then I chrono the load at 400-500 yards on steel. Hopefully, the numbers are tight, and the steel grouping is good. If so, I'm done. If not, I keep working at the load until it groups good at 4-500. I believe the cartridge you choose has a lot to do with the consistency of the chrono numbers, and tight performance down range.
If I see a powder/bullet combo that shoots shotgun patterns at 100 yards, all the way thru the charge range, I'm immediately moving on.
If I see a powder/bullet combo that shoots shotgun patterns at 100 yards, all the way thru the charge range, I'm immediately moving on.
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Deleted member 10043
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Absolutely the best post I've seen in years. Check out the 500 yard thread if you can find it. LOL!!!!!
Know your rifle. Practice with your rifle. Believe in your rifle. Make the shot.
My point is merely that many shoot 3-5 shots and announce an SD value. If one shot represents 33% of your sample, you can't have an 80% confidence interval. While the chrono will calculate it, your SD is not relavent. Even taking 5 shots, those may or may not be representative of the whole sample. Stats relies on a preponderance of data, not what reloaders typically generate.
Is SD relavent? Absolutely, but most posted SDs are bunk. This is the duality I was attempting to convey in my earlier post.
I have to agree with you, I see so many people shoot 3 or 5 shots across the chronograph and brag about the numbers. I just had this discussion with a guy I'm trying to help with load development. I shoot 10-20 to see where I'm at and I don't obsess over trying to get really low numbers like some people.
I'm not going to disagree with statistical relevance on a 5 shot group by itself
But if every time I'm at the range I throw the chrono on for only 5. Same load same everything. And the SD (and average) is consistant, even from virgin to 1x and 3x fired brass. Then it becomes relevant and I'm merely confirming my load over and over again over a period of time and multiple firings and In this case i think 5 is more than acceptable
Or if I'm working in a .2gr node in 3 consecutive .1gr 5 shot groups. SD becomes relevant there as well looking across the data for all 15
If you're going to bother paying attention to SD and ES then you need to be shooting 10 or more over the chrono.
For load development and for PRS style matches an ES under 20 is fine in my opinion.
As far as checking your loaded ammo for matches goes I do the following: most my matches are 70-90rds I'll load 100 and shoot 10 for quality control and to get my average speed. The way I shoot them is 1 from each row so I can check from start to finish from my entire loading session how well me and my scale loaded everything. Just because you spend a ton on your powder throwing set up doesn't mean something weird may happen. All should be good and you can make sure your speeds you got from your chrono match up to what you should already have in your preferred program, if you feel the urge to change it a little then do so.
As far as usefulness, for me I'm not quite good enough to be worrying about winning since I usually finish middle of the pack so a 20 ES wouldn't worry me for a match but I really wouldn't want one higher than that.
However those small diamond plates are easier to hit the smaller your vertical is so if you are gunning for a top place at a match I'd be trying to get your ES under 10. Corner hits on a diamond always feel good lol.
If you have decent brass, primers, dies, and a scale it really shouldn't be hard to get your ES under 10 even for a beginner.
For load development and for PRS style matches an ES under 20 is fine in my opinion.
As far as checking your loaded ammo for matches goes I do the following: most my matches are 70-90rds I'll load 100 and shoot 10 for quality control and to get my average speed. The way I shoot them is 1 from each row so I can check from start to finish from my entire loading session how well me and my scale loaded everything. Just because you spend a ton on your powder throwing set up doesn't mean something weird may happen. All should be good and you can make sure your speeds you got from your chrono match up to what you should already have in your preferred program, if you feel the urge to change it a little then do so.
As far as usefulness, for me I'm not quite good enough to be worrying about winning since I usually finish middle of the pack so a 20 ES wouldn't worry me for a match but I really wouldn't want one higher than that.
However those small diamond plates are easier to hit the smaller your vertical is so if you are gunning for a top place at a match I'd be trying to get your ES under 10. Corner hits on a diamond always feel good lol.
If you have decent brass, primers, dies, and a scale it really shouldn't be hard to get your ES under 10 even for a beginner.
I must really suck at loading because I don't think I have a single load with single digit es over a 10 shot string.
I may just have dumb luck, I don't know but as long as I stick to charting my velocities during load development, load in the flat spot, and use SRP alpha brass, gmm primers, and throw .1 under and then trickle the last 1-3 kernels of powder on my charge master I've always had ES under 8. When I used lrp brass my es was always under 12, I'm not sure if that's because of primer size and all of that or just different lots of brass but that's how it was.
I still can't shoot good enough to get into the top 10 at any matches so it's not helping me much lol
Carl Zant in his article on the precision rifle blog explains this very thoroughly and it seems that to a point there are diminishing returns getting the sd below 10. My current sd is at 6 and I figured that on a target my deviation in bullet drop is only .5 inch and at 1000 yds my average deviation is 5 inches. Brian Litz' s WEZ tool showed the hit probability extremely high at this level and improving sd further makes very little sense compared to improving say wind calls which makes a dramatic difference between 1 and 3 mph accuracy
I treat it similar to this
I looked at my loads across all days...if it gives me an sd or 3 and an Es of 13 one day but 15 and 58 the next time out...it’s not a good consistent load
I’ve got a batch of old mixed lot/firings trash brass and no matter what load work up in do in it the Sd is high and the Es is generally 60-80...I use it for small club matches and stuff when I don’t want to pick up my brass...it shoots great at 100 yds, but I can 100% tell the difference in consistency past 500 vs my normal loads that are single digit sd and Es in the 15-25 range, especially if the targets get smaller
D
Deleted member 10043
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It takes approx. 30 shots to barely reach a 90% confidence interval. It also a measurement of the rifle and shooter. An initial proud .3 MOA group will probably jump up to .6 MOA with a 90% confidence. That is at 100 yards. It will open up at distance.
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If it can't be proven through a scientific method than it is just voodoo testing.
A good chronograph is nice but not mandatory. I often see people shooting lights out at distance that have not chronographed. Actually, all they do is write down their dope. Inspect spent cartridges, etc.
Here is an under used tool that will deflate your ego.
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If it can't be proven through a scientific method than it is just voodoo testing.
A good chronograph is nice but not mandatory. I often see people shooting lights out at distance that have not chronographed. Actually, all they do is write down their dope. Inspect spent cartridges, etc.
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I think the chrono and SD/ES numbers are just an added tool and benefit for me when working up a load because for me it all comes down to time and cost. I do not want nor have the time to spend all day chasing a load and seeing how it groups at distance on paper. I really like the method Scott Satterlee came out with on the chrono and I have developed that same method in my load development the last few years. I never did pay attention to how well it groups at 100 because my opinion is if you’re a fairly decent shooter then everything groups well at 100. I shoot 3 rounds of my chrono in .2 grains increments and look for where it flattens off. My last load work up 43.2 and 43.4 where almost identical so I pick the middle and go chrono it and I’m done. Took me about 25 rounds and I have a load that has been very consistent. I agree with many statements above that a consistent load at distance is gonna have lower numbers so why not look for them now and save time? Just my thought.
