ES vs accuracy

Shadowwalker

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Which result would you consider best based off this target?
I evaluated ammo for Lapua for 4 years, bench shooting thousands of rounds of every manufacturer in a 104 lb rail gun in a controlled environment. One of the things you learn real fast is one test means nothing. Repeated tests where trends form are the true evidence. Same as guys posting their best group ever......that is not the guns true potential.
 

redneckdan

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I did that once and it worked. But it cost my 50 FPS. I’ve seen where some guys say and ES of 20 or better is fine for hunting and I really want to agree. But I’ll load a few batches of my best groups and test at distance. Ironically, the load that produced the largest group went 3/3 at 730 and 950 last month. So fingers crossed that something else will hold together at distance
My experience has been a load that groups okay at 100 but has good statistics tends to hold together better at distance. I don't totally understand why this is. This load is running at 2950fps with and SD of 4. .020 off the lands. .090 off the lands is better yet but the base is below the neck junction.

The first picture is a dtac load at 100. Not bad, not great.

2nd picture is the same load at 500. Looks pretty okay to me.
 

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BrentM

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Chasing es and sd is an interesting issue. Many people shoot a small sample and claim they have super low sd but over time and conditions etc the sd is much much larger. People will just not admit it generally. To me most of your es info is pretty close and I'd choose the accuracy plus es, but also with a small sample it may not be repeatable until you test it enough. For example, 100 yard groups mean very little to me. I'd want to test the best group or lower es at distance. I would also want to look at seating depth, if not already done, to see if the lower es will tighten up.
 

Paper boy

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Which result would you consider best based off this target?
Your inner 9 0'clok as compared to you 12 o'clok groupes, shot with the same powder but different amout tell the. Stay with 12 o'clock. Cool of your rifle and do it again to be sure. Crono the resuls.
 

Jumpalot

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I threw away my chronograph a long time ago as it caused more frustration then it helped. Had loads that were accurate but bad ES and had loads with good ES but bad accuracy. I check for accuracy at the furthest distance I'll be shooting, if I see some vertical dispersion, I'll adjust charge weight a little. Once I'm satisfied with the accuracy, I start validating drops. Some of my best loads had very mediocre ES and SD. I've also never had a chronograph (Magnetospeed and Oehler 35) match my proven drops. A popular gunsmith on here told me once when he built me a rifle that I can chase numbers or accuracy. He recommended chasing accuracy.
 
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Paper boy

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I agree, this is a matter of mathmatics, an almost exact science, ballistics are only theoreticle based on math. There will always be variables when you consider the many conditions to consider, consider, consider, consider, and so on, and so on!
 

redleg1013

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The ES is going to directly affect your precision at distance, meaning your group will be either better, worse, or inconsistent (worse). Getting your ES down will ensure that the harmonics of the barrel are closer to identical from shot to shot. I've had promising 100 yard groups become turds at 300+ it can be frustrating but this is part of "the fun" of hand loading.
Best advice is to take two or three of your most promising and stretch their legs a bit, see what holds at 300-500 yds, and what falls apart. Remember vertical is velocity, and lateral is length as far as dialing in your load. Technique in both loading and shooting are vital to developing your best load. Personally I quit 100yds grouping and have just gone with Audette ladders at 300, then I play around to tighten them up a skosh.
 

MTbackwoods

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Ironically, the load in the center proved very accurate and repeatable on steel at distance. Maybe it improves with distance. Idk. I loaded 9 of each of my best 2 groups. I’ll see how they do at distance this weekend. I’m thinking about shooting groups at 730 on paper. I’ll report back with results
 

Jumpalot

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So by everyone's logic, if you have a good grouping load at distance, then you have a low ES/SD. So, why do I need to chronograph and see a printout to know that. I'm going to tweak my load either way until I see what I want to see. My point is, once I have a load that will shoot under MOA with an under 9lb hunting rifle off a bipod and rear bag and I do my job out to however far I've predetermined is my max hunting range, then I don't care what my ES is. I'd rather shoot at said distance, get some trigger time, actually see what the load does at said distance instead of looking at a printout screen. What I love about our sport/hobby is there are many ways to get to our desired goal. I also choose not to do OCW or Ladder tests. Just my preference. Yes, I've read a lot of Litz and even emailed with him about a ballistics program he was part of before he did the Applied Ballistcs program. They had an old BC for the first gen 300 grain 338 bullet and I couldn't get my drops on the program to match with what I was actually seeing. Spoke with him and he found the problem and corrected the program in about two days with an update. Great guy!! But shooting over a chronograph and looking for ES wasn't going to show me the actual problem. Regardless of how you choose to go about it, go enjoy the outdoors, shooting and learn everything you can so you can share with others. The only problem with our sport/hobby is, sometimes if you don't do it a certain way others say to do it then the you know what hits the fan. Keep us posted on your progress and your process. I'm watching to hopefully learn something new too. Good luck and have fun!!
 

nt7332

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So by everyone's logic, if you have a good grouping load at distance, then you have a low ES/SD. So, why do I need to chronograph and see a printout to know that. I'm going to tweak my load either way until I see what I want to see. My point is, once I have a load that will shoot under MOA with an under 9lb hunting rifle off a bipod and rear bag and I do my job out to however far I've predetermined is my max hunting range, then I don't care what my ES is. I'd rather shoot at said distance, get some trigger time, actually see what the load does at said distance instead of looking at a printout screen. What I love about our sport/hobby is there are many ways to get to our desired goal. I also choose not to do OCW or Ladder tests. Just my preference. Yes, I've read a lot of Litz and even emailed with him about a ballistics program he was part of before he did the Applied Ballistcs program. They had an old BC for the first gen 300 grain 338 bullet and I couldn't get my drops on the program to match with what I was actually seeing. Spoke with him and he found the problem and corrected the program in about two days with an update. Great guy!! But shooting over a chronograph and looking for ES wasn't going to show me the actual problem. Regardless of how you choose to go about it, go enjoy the outdoors, shooting and learn everything you can so you can share with others. The only problem with our sport/hobby is, sometimes if you don't do it a certain way others say to do it then the you know what hits the fan. Keep us posted on your progress and your process. I'm watching to hopefully learn something new too. Good luck and have fun!!
Hey brother there is always several ways to skin a cat and your logic is sound. The correlation between low ES/SD in small groups at distance is right on. I choose to run chrono on initial load work, to not only see where I am at velocity wise but also how consistent the load is. Shooting groups at 200, if u have a 1/4 moa load with a SD or 2 is prolly going to do pretty good at distance. Again this is just my experience. But from what I have seen it just saves time in shooting rounds for no reason not using one. I have shot some nasty one hole groups at 200 yds with stupid high ES. If I didn’t have a chrono to get that data from I might go try that at distance only to be disappointed because of vertical. You do have a valid point though and your method will prolly induce more trigger time which directly = fun!
 

rsmithsr

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that statement is not true.
good groups DO NOT MEAN low es/sd.
[/QUOTE="Jumpalot, post: 1929293, member: 4867"]
So by everyone's logic, if you have a good grouping load at distance, then you have a low ES/SD.
[/QUOTE]
 

nt7332

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that statement is not true.
good groups DO NOT MEAN low es/sd.
[/QUOTE="Jumpalot, post: 1929293, member: 4867"]
So by everyone's logic, if you have a good grouping load at distance, then you have a low ES/SD.
[/QUOTE]
What is your theory behind that statement? Good groups at 100 absolutely not, at that distance ES has little affect. However, at 1k and out of you have high ES that target will tattle quick as your mistress when u don’t pay to get her nails done. Vertical spread has a very close relationship with variances from round to round velocity differences. Just trying to understand and maybe learn something new from your view! Thanks
 

MTbackwoods

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Hey brother there is always several ways to skin a cat and your logic is sound. The correlation between low ES/SD in small groups at distance is right on. I choose to run chrono on initial load work, to not only see where I am at velocity wise but also how consistent the load is. Shooting groups at 200, if u have a 1/4 moa load with a SD or 2 is prolly going to do pretty good at distance. Again this is just my experience. But from what I have seen it just saves time in shooting rounds for no reason not using one. I have shot some nasty one hole groups at 200 yds with stupid high ES. If I didn’t have a chrono to get that data from I might go try that at distance only to be disappointed because of vertical. You do have a valid point though and your method will prolly induce more trigger time which directly = fun!
Agreed. I decided to mess around with RL33 in my 7 mag and see how it did. It shot some pretty good groups and the picture shows one. This was shot at 100 yards. Now I think we can all agree, that’s a great group from a hunting rifle that is also a magnum. But the ES was 55 FPS on that grouping. So even at my personal hunting limit of 800 yards, that’s not a good load. That equates to a minimum of 4” poi shift from poa. I require something better than that
 

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