What's causing these ES numbers? Help me analyze, please

[devldogs55]

I've got a brand new rifle that I've been working up a load for. I am trying to get a good ballpark load to shoot about 100-150 rounds through before I set my sights on my final COAL/jump. Even just in the first 60 rounds my bullet has gone from touching the lands at 2.227 to now 2.232. What I'm experiencing right now is some pretty high ES numbers, and I'm trying to get them down. So I'll run you through everything I've got and how I'm loading.. any variables I can think of and let me know what you think, if you don't mind.

Rifle:
.308 in a Broughton 22" comp contour 1:10

Load:
Winchester brass (unfired) and annealed
All trimmed to same length
Headspace bumped back .002 from fired case
Fed 210 primers
.003 neck tension
Nosler 175 RDF (factory seconds/blems)
44.8gr Varget
Seated to 2.207"

Chrono: Labradar

I am fixated on these 175 RDFs and the huge variation in bullet weight I get on these blems. Each box of 100 has a variation of about 1.2 gr from the lightest to heaviest bullet. They very well may NOT be the problem, but that's another reason why I'm here - hopefully we can figure that out. I am using Redding Type S sizing dies, Forster competition seating die, and throwing charges from the Chargemaster at .1 gr under and then trickling up the last grain and stopping the second it tips up to 44.8gr. This is another point that could cause my issue which I'm trying to remedy. I ordered a GemPro 250 and I'll be testing next week to see if I can get more accurate throws. I also plan on pulling a few bullets from what I have loaded now and weighing those charges on the GemPro when it gets here to see how consistent they were.

My seating depth is +/- .002 from 2.207 which put my jump at .020 from my initial measurement. Now it's a bit more - but I've heard these RDFs really like to jump. Is that something that I should change? I think my .002 variation is from the LNL press I'm using. I know a lot of guys hate on the LNL and it's kind of frowned on to load precision ammo on a progressive, but I don't have this ES issue with other precision rifle loads where I was using a 178 AMAX in my other .308. That rifle has some great ES numbers.

So I've attached my report from my Labradar for you to take a look at. Am I crazy to blame these blem RDFs? It annoys the hell outta me that those vary so much and my 175 VLDs are all within .1gr of each other.

 

[918v]

Over annealing causes huge ES

 

[devldogs55]

The brass is brand new and I didn't anneal any different than I usually do. These have only been annealed once before sizing.

 

[Darkside-Six]

Sounds like that charge weight is not your optimal load then. I would load up 5 round groups in .1 grain increments and go .3 up and .3 down from where you're at. Shoot them over a chrono and see what the numbers do.


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[918v]

The brass is brand new and I didn't anneal any different than I usually do. These have only been annealed once before sizing.

How do u usually anneal?

 

[GhengisAhn175]

I'm not familiar with out the labradar spits out data and it looks like you gave us a sample size of 40.

first off, an SD of 9mfor 40 shots is very good.

ES just shows the lowest shot to highest shot difference.

so out of 10 rounds if I had all of them hit exactly at 2900 FPS AND One of them happened to go 2850 or 2950, I'll have an ES OF 50 but still a very low SD.

In your chart you had 2 rounds hit in the 2650's. The rest were closer to the average with some in the 60's.

Some questions:

how did you settle on 44.8? Did you do load development and 44.8 was the most stable?

how did you settle on only a 20nthoussndth jump? Did you do a seat depth test and 44.8 @ 20 thousandths off the best performer?

why are you running 3 thousandths neck tension? Personal preference? 1 or 2 is ideal in my opinion.

not sure how you're sizing but are you also using an expander ball/mandrel?

My guess is neck tension is the culprit. the few odd shots from such a HUGE sample size is my reason. And on that, I'm going to assume you're sizing the neck on the outside and not touching the inside again (SWAG guess from lack of info)

the next guess is seat septh.'I think tweaking it may optimize if the first guess is wrong.

 

[devldogs55]

Sounds like that charge weight is not your optimal load then. I would load up 5 round groups in .1 grain increments and go .3 up and .3 down from where you're at. Shoot them over a chrono and see what the numbers do.


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I'm going to have to do another OCW test I'm thinking.. but the charge I selected for these 40 rounds was the result of a OCW test. They honestly all had pretty good groups, but the 44.8gr was a tiny bit better and it was kind of the spot where my velocity didn't jump up quite as much from the previous load. I started at 44.2gr and each .2gr jump the average velocity went up steadily until I went from 44.6 to 44.8 - it just barely crept up. ES was hard to go by on the OCW test because even in a 5 shot test my best ES was 18.

I'll be doing another OCW though..

 

[devldogs55]

How do u usually anneal?

I use an Annealeeze and I set it up with 750* tempilaq on the inside of the case neck.

 

[devldogs55]

Some questions:

how did you settle on 44.8? Did you do load development and 44.8 was the most stable?
I ran a OCW test and tested from 44.2 to 45.0 gr in .2gr increments. They all yielded decent groups, but the average velocity (out of 5 shots each load) rose steadily for all .2gr jumps. Once I went from 44.6 to 44.8 it rose about half of what the other velocity changes were. ES was still at least 18 on the test loads.

how did you settle on only a 20nthoussndth jump? Did you do a seat depth test and 44.8 @ 20 thousandths off the best performer?
With this bullet profile I have heard they like a good jump. I could be completely wrong, but I settled on that to start. Typically once I find a node for charge/velocity I play with seating depth and neck tension.

why are you running 3 thousandths neck tension? Personal preference? 1 or 2 is ideal in my opinion.
It was just what works for me on my other .308 and I went with it. I planned on playing with this aspect after I found my node.

not sure how you're sizing but are you also using an expander ball/mandrel?
My Redding Type S die is set up with no expander ball.

My guess is neck tension is the culprit. the few odd shots from such a HUGE sample size is my reason. And on that, I'm going to assume you're sizing the neck on the outside and not touching the inside again (SWAG guess from lack of info)
That is a possibility I'll look into more.. that does make sense. Thanks for taking a look.

the next guess is seat septh.'I think tweaking it may optimize if the first guess is wrong.

 

[Fursniper]

Well, you're under 10 on your SD so thats good. I'm wondering what made you settle on the 44.8 grains? You're fixating on the bullet weight variation, have you checked the brass?

 

[918v]

I'd redo the test with new unaltered brass.

 

[devldogs55]

I'd redo the test with new unaltered brass.

I'll work up a sample lot of some with less neck tension that are annealed and some with the same new neck tension without annealing.

 

[GhengisAhn175]

Haha ... I'm pretty sure it's the lack of neck turning and no expander ball.

so not to steal this thread but there's another one where we were discussing neck turning..

THIS.. is a perfect example of what I'm talking about. If you neck turn then you don't need to fuck with an expander balls IF you don't neck turn you need to account for the neck thickness differences by making the inside neck tension even.

Ill bet a box of Hornady 200 ELD-X that this is the issue.

one other thing about seat depth: I always recommend up start at 20 thousandths and then only seat deeper during tests. And yes the RDF's like jump and normally people are starting at 30 thousandths minimum but s couple like yourself found 20 thou okay.

If im right you owe the 3 closest hide members to you a case of beer each.

 

[devldogs55]

Well I don't neck turn and I don't really plan on starting. Honestly if neck turning is what it takes to get my ES down then I'll live with my current ES. I have single digit ES on my other .308 (... ok it's usually around 12) and have never neck turned.

One thing I didn't mention is that I get my neck tension down in two steps. So once it's fired, I don't take neck tension down more than 5 thousandths at a time. So I run the brass through the sizing die twice. The first time I do have an expander ball on. The second time, I remove it. Not sure if that makes a difference.

 

[GhengisAhn175]

Then try running an expander ball and see what happens

 

[devldogs55]

I'll give it a shot. I'm not trying to argue and say you're wrong - but I just don't know if I can justify the cost of a neck turning setup and then, most of all, the effort to turn them.

 

[918v]

What are you going to turn? Win necks are already incredibly thin.

Try more neck tension not less. The thinner the neck the more neck tension you need to maintain the same bullet pull.

 

[IanHusaberg]

Your using Factory 2nd/blems bullets and are wondering why you have variations? Don't know why your being so cheap with your components. Try Lapua brass!

 

[djarecke]

I'll give it a shot. I'm not trying to argue and say you're wrong - but I just don't know if I can justify the cost of a neck turning setup and then, most of all, the effort to turn them.

You don't need to neck turn, you just need to run an expander through after you size the necks to get a more consistent neck tension. Re-read what Ghengis said....

 

[Downzero]

A single digit SD and you're complaining? Forget your extreme spread and drive on.

Oh and by the way, your load is probably too hot. Back off to your next lower node or you're going to beat your brass up.

 

[GhengisAhn175]

Down zero,

ES is just as important as SD. He has a wide ES yet a 9 for an SD. Definitely something that can be fixed. If his ES was lower (and frequencies) then I'd have said drive on you're fine. Especially with 40 recorded Shots.

go look at his recorded individual shots and see why that would be a concern for long range Shots.

 

[devldogs55]

So I've pondered the advice I've received here all day, and I thank you all for it. I think I've got a game plan. First off, I think even if the 175 RDFs aren't the culprit, the variation in the weight is just going to bug me too much, and it will be in the back of my head.. so I'm selling those. Gonna try some 175VLDs and see if the BC of the 178 ELD-Ms are all it promises.

I'll keep the Winchester brass for rainy days, but I'll move back over to Lapua brass. I'll err on the side of annealing less rather than risking over-annealing, and I'll run an expander ball when I resize. I'm going to take a close look at my neck tension and try a bit less with Lapua brass.

Ian made a good point.. it's not fair to my stress levels and anxiety to be using seconds and Win brass and be wondering why I have the ES numbers. If there's an issue, I should be taking out all the variables I can control right away, and it will help me pinpoint the changes I need to make.

 

[GhengisAhn175]

It's not the bullet weight or it being seconds. but it seems like you've made up your mind.

youre changing a ton of variables so you need to start over from scratch

 

[devldogs55]

I don't know.. do you really think a 174.2gr bullet fired right after a 175.6gr bullet won't have any variation in velocity? Because that's what I'm seeing. I'm not being sarcastic.. I truly don't know.

I did forget to mention that I'm shooting suppressed. I doubt that makes any difference though.

 

[918v]

According to QL, your bullet weigh variance accounts for only 6 FPS of ES.

 

[devldogs55]

Very well.. that about settles that. I suppose if I figure out my issue I can solve that 6fps issue fairly easily by sorting if I needed to.

 

[Downzero]

Down zero,

ES is just as important as SD. He has a wide ES yet a 9 for an SD. Definitely something that can be fixed. If his ES was lower (and frequencies) then I'd have said drive on you're fine. Especially with 40 recorded Shots.

go look at his recorded individual shots and see why that would be a concern for long range Shots.

ES and SD measure the same thing. An SD of 9 isn't something on which meaningful improvement is likely even possible.

For a normally distribution, SD tells us that 99+% of the observations will be within +/- 3 standard deviations.

9x6 =54

For a load with an SD of 9, an ES of 43 is, therefore, on the low end of what is "normal" given how statistical functions work.

In other words, shut up and drive on.

You don't need "help" analyzing because you've already done the analysis.

You've verified empirically what the theory could already have told you, which isn't a bad thing at all. SD doesn't tell you the range of observations that are normal. +3 and-3 x your SD does.

 

[Downzero]

https://en.wikipedia.org/wiki/Standard_deviation#Rules_for_normally_distributed_data

 

[devldogs55]

I appreciate your thoughts, but I have to disagree. You don't have to go far on this board to find a much tighter ES than mine.

I'm not trying to improve my SD, I'm trying to improve my ES

 

[GhengisAhn175]

I don't think you're understanding my point downzero

Lets agree to disagree I've said my piece on this thread already

 

[Darkside-Six]

I'm going to have to do another OCW test I'm thinking.. but the charge I selected for these 40 rounds was the result of a OCW test. They honestly all had pretty good groups, but the 44.8gr was a tiny bit better and it was kind of the spot where my velocity didn't jump up quite as much from the previous load. I started at 44.2gr and each .2gr jump the average velocity went up steadily until I went from 44.6 to 44.8 - it just barely crept up. ES was hard to go by on the OCW test because even in a 5 shot test my best ES was 18.

I'll be doing another OCW though..

That is why I don't do OCW tests. anything can group well at 100 but if the ES and SD is high then it will fall apart at farther ranges. you may have to sacrifice some MV to get your perfect load. I know we all chase speed but often times I find my most accurate loads are on the slower side of what I'd like.

I would do this if I were you.

Load up 5 round groups starting at 44 grains and go to 45 grains. yes, that is 50 rounds but still.

Shoot a warm up group to get your barrel up to temp and get your chrono going.

Then shoot a random group. Pick one in the middle and shoot it over the chrono.
Have a piece of paper with each charge weight written down in order.

Fire the groups in random order with adequate time between to let your barrel cool.

Write down each groups average MV, SD, and ES numbers.

After you've shot all the groups look at your paper. You should see a spot where your numbers walk right down and that is where your load is.

 

[JCCinOhio]

To see how/if bullet weight matters you could sort some bullets by weight.. or number your rounds based on bullet weight and then you'd be able to use the LabRadar output to group data from like bullet weights and figure SD/ES on those groups.

 

[spife7980]

Im with Ghengis, you squeezed all of the brasses imperfection to the inside and then left them there to impart uneven tension on the bullet. Run the expander ball so that it pushes those imperfections to the outside and your provide your bullet with an even surface to interface with. Thats why they include the expander ball.

And it isnt the bullets. Weight sort them like JCC just said to prove it to yourself.

Also, this is new brass. Thats pretty good for factory crap winchester on a new barrel.

 

[devldogs55]

Alright I believe ya. Ghengis is convinced me yesterday to give it a shot with the expander ball before I do anything crazy like sell my stock of RDFs off. I'll report back Thursday or Friday

 

[spife7980]

I mean, it always could be that the barrel just doesnt like the bullets but there are much more glaring issues to address first, IMO. Target pictures are always nice to look at too

 

[devldogs55]

I'll make sure to bring pictures later this week from the next trip out. Once I get this figured out, I'm also going to have to figure out why my dope on my Kestrel is so wrong at 300yd. I'm guessing I measured my sight height wrong or something like that

 

[djarecke]

I'll make sure to bring pictures later this week from the next trip out. Once I get this figured out, I'm also going to have to figure out why my dope on my Kestrel is so wrong at 300yd. I'm guessing I measured my sight height wrong or something like that

Make sure you're zeroed at 100 yards and then shoot as far out (i.e. close to transonic) as you can, and double check your data. Wind, DOF, etc. all need to be inputted properly for dope to work well for you.

A 300 dope check is so close in, it's not a very meaningful data point to true your ballistic solver.

 

[Downzero]

I appreciate your thoughts, but I have to disagree. You don't have to go far on this board to find a much tighter ES than mine.

I'm not trying to improve my SD, I'm trying to improve my ES

They measure the same thing. It is impossible to improve upon one, empirically, without the other.

I don't think you're understanding my point downzero

Lets agree to disagree I've said my piece on this thread already

You don't, either.

Because you don't know what you're talking about.

An ES of 42 is within 4 SDs of the mean velocity. 95% of your observations will be there. It is entirely normal.

Maybe more consistent brass will reduce your SD from 9 to something less than that. ONLY that will reduce your ES.

If you see other people who advertise lower ES numbers, it's because they don't have a sufficient sample to really show actual ES. I bet if you fired 5 shots, you could demonstrate a lower ES, but you wouldn't have the full picture.

In other words, you're worrying about nothing.

 

[GhengisAhn175]

No down zero, YOURE not the one understanding how ES AND SD correlate with each other. You didn't Even read my earlier post.

his sample shot size is 40 rounds.

Out of those 40, 8 fall out of a 20 +\- FPS from his average velocity.

I already said he's found a good node and if he wants to leave it alone he can. However if he wants to tighten it up he needs to uniform neck tension from the variety of ways listed.

Going back to his 8/40 (which is 20%) he has 32/40'which fall under the 20 FPS +\- (actually closer to a mean average of 13) which gives him a good SD of 9.

if you know anything about what ES means it just means the difference between the highest and lowest round.

SD is the deviation from all the rounds together.

ES AND SD ARE NOT LINKED TOGETHER.

Example: he had an ES of 100 and his SD was 9 and it's because only one of his 40 rounds he undercharged poorly,
then I'd say "hey you fucked up round #17, that was the only one that was outside the average FPS And that's why you have an ES of 100, my recommendation would be to leave it alone and that one round is a fluke".


You up don't even have to read a single thing I typed. Go look at his velocity chart. All the information is right there; don't just stare at the 9 SD and say "it's single digit don't worry about it".

You arent even considering the second and third order of effects from just leaving it as is

 

[devldogs55]

Alright, I've pulled all remaining bullets and re-tooled here. I just received my Gem Pro 250, and while it's not the top of the line necessarily - it sure pointed out a huge spread in charge weights that the Charge Master just doesn't account for. What I thought was a lot of 30 rounds with 44.8gr was actually anywhere between 43.6gr and 45.4 gr. Talk about some major ES! I pulled all 30, and ran them through the sizing die again with an expander ball on there. I am now running .002" neck tension, and I am confident the powder charges are within 1 or 2 kernels of where I wanted them. I've got 5 rounds each of 44.0/44.2/44.4/44.6/44.8/50.0 to try out, and I'm on my way out to the range within the next half hour. I'll be sure to post results when I'm back.

Thanks to everyone so far with the help!

 

[GhengisAhn175]

Did you ensure all grains were out of the cases or just do a blind dump?

 

[Darkside-Six]

^ what he said. That's a pretty big spread for a chargemasters. I run chargemasters and have never seen it be that far off personally. My ES numbers are all under 15.


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[devldogs55]

I checked with a flashlight to see if any were in the flash hole. I'm still at the range now, but I'm already seeing fantastic results. Groups are much better, and my ES is phenomenally better. I know it's only 5 shots each, but this is what I'm seeing already in only 3 of 6 charges.

Is is absolutely possible to improve upon an ES of 40 even with a SD of 7.

I think my chargemaster problem may have been the solution to a problem I maybe didn't even have. I was throwing .1 gr under target with the CM and trickling up until it turned over to the exact target weight. I think the problem was that it turns over at inconsistent weights, but throws them more accurately from the get go. The Gem Pro was a big help today.

 

[GhengisAhn175]

Glad your issue is fixed at least. Ensure your groups are 1/2nmoa or better.

chronon#'s alone don't cut it.

Two thing to consider:
drafts when weighing (AC, excessive movement)
double check weights (completely taking off and back on) AFTER final trickling. Don't trickle up to weight and put into case.

 

[tylerw02]

The brass was annealed at the factory. Not reason to anneal again.


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[devldogs55]

I definitely was not taking the pan off and putting it back on, and it sounds like that was causing a lot of variation. I did do that once I got the Gem Pro, though.

Tyler, I don't think Winchester anneals factory brass.

Anyhow. I found one load that performed very well today. 50.0gr, Avg: 2698, SD: 5.4, ES: 12 and group was about .3". No pressure signs, no sticky bolt lift etc... I'll play with that some more tomorrow.

 

[918v]

Winchester does anneal the brass at the factory.

 

[tylerw02]

I'm pretty certain they do. Never heard of a company that doesn't. They polish it after its annealed, getting rid of the marks/discoloration.


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[devldogs55]

Hmm good to know - I had no idea. Especially since they polish them, my Lapua brass has the obvious annealing coloration - just never noticed that on the Winchester stuff. I'll keep that in mind when I load the rest of the new Win brass

 

[spife7980]

Anyhow. I found one load that performed very well today. 50.0gr, Avg: 2698, SD: 5.4, ES: 12 and group was about .3". No pressure signs, no sticky bolt lift etc... I'll play with that some more tomorrow.

How far are you off the lands? Do a test .1 either side to see if it dives off the edge of a cliff or if youre in a comfortable node. Then a depth test to ensure that there isnt a more optimal load hiding just around the corner but .3 moa with a SD of 5 is pretty darn good.