Es/Sd 33/10.5 Happy or no?

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10 round string. Es/Sd 33/10.5. Say in theory I'm at the top of my node would dropping .1gn of powder decrease my numbers. Would you be happy with the current numbers for long range 1000 yard shooting from a so so shooter?
 
My personal preference is an ES of under 20 and a single digit SD so no, I wouldn't be happy with that. That's .3 mil /1MOA difference at 1000.


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10 round string. Es/Sd 33/10.5. Say in theory I'm at the top of my node would dropping .1gn of powder decrease my numbers. Would you be happy with the current numbers for long range 1000 yard shooting from a so so shooter?

More importantly, instead of goading to get those numbers tighter, I would ask how you came upon this load. Did you perform an OCW or Ladder test? Are you truly in your accuracy node? What steps toward a minimum ES/SD did you take in the actual loading process at your workbench?
I've had loads that shot lights out that when chrono'd had only one round that made ES wider than I would have liked. Did you have a sole offending or is that ES from a general spread?
 
I did a ladder test. It was the best group in my ladder test. Only chronod after I picked the best group. Used Forster FL die(non bushing), Forster micrometer seating die, RCBS Chargemaster. Trimmed to length. That's about it. The Es was from a general spread. It was 90 degrees plus the day I tested. Not sure if that makes a difference.

2821
2827
2826
2808
2801
2834
2827
2830
2818
2812
 
Now that I type out the velocitynunbers if that 2801 and 2808 weren't in there the numbers get a lot better. Es would only be 22 if I took those two shots out
 
I've used multiple Chargemasters over the last few years. I finally got the best in speed and accuracy by trial & error reprogramming and employing the bushings offered by member MDM. Still, they vary more than enough to produce the ES numbers you have.
Now, if you are at the top of the node you are in the wrong place, IMO. Go to the middle of the node you found in the ladder test and that should give you the leeway you need to make things happy.
 
Up in Canuckistan (my homeland) a discussion of this nature took place and the thread pretty much blew up with theories, use of chronies, etc.

I was out at the range on Friday and do some more testing and ran 40 or 45 rounds over the chrony (Labradar). I think my ES was 50 and my SD was 14 or something like that. I am not super pleased with the numbers and will be trying BR2s over the 200s to see if that will help. I am also shooting new brass so I think I will round out the necks with a mandrel before I load them.

However, I am starting to think that 5 or 10 round chrony tests are not indicative of the true SD/ES of ammunition. If I were to limit the sample to 20 rounds I get back to the ES under 20 and SD of single digits but seeing as we shoot many rounds during a match the reality is probably quite different.

Looking at the WEZ analysis on PRB (which I know is not popular here) the benefits of reducing your SD below 15% is diminishing (especially once you go below 10).

However, I will continue try to get things below 10...
 
Up in Canuckistan (my homeland) a discussion of this nature took place and the thread pretty much blew up with theories, use of chronies, etc.

I was out at the range on Friday and do some more testing and ran 40 or 45 rounds over the chrony (Labradar). I think my ES was 50 and my SD was 14 or something like that. I am not super pleased with the numbers and will be trying BR2s over the 200s to see if that will help. I am also shooting new brass so I think I will round out the necks with a mandrel before I load them.

However, I am starting to think that 5 or 10 round chrony tests are not indicative of the true SD/ES of ammunition. If I were to limit the sample to 20 rounds I get back to the ES under 20 and SD of single digits but seeing as we shoot many rounds during a match the reality is probably quite different.

Looking at the WEZ analysis on PRB (which I know is not popular here) the benefits of reducing your SD below 15% is diminishing (especially once you go below 10).

However, I will continue try to get things below 10...

Just speculating here, but I think a lot of what you're reading is getting lost in the translation, everyone seems to want to post their new and improved method of finding the perfect load. I believe in the OCW test, and run a combo of a ladder and ocw at 500 yards, I also believe in the barrel time theory, but here is an area we cannot truly measure and must rely on a program like Quickload for assumptions.
Here's the deal, you say you shot 45 rds over your labradar, most likely at 100 yards waiting for magical numbers to transpire. If you were to get the components, brass, bullet, primer, powder charge, etc.. to get into a pressure range that your barreled action likes, the numbers tighten on their own. Get a larger pc of steel, set at 500 yards, draw a level line across it, then mark some aiming points, then load 3 charges each of varying weights in succession, set the LR up, and shoot 2 of each, the 3rd for a called biff. When you see 2, or more favorably 3 charges that hold vertical at that distance, scroll back through LR and you will see tighter numbers. Realistically, now picking a charge in the middle of this will work, but now, adjusting seat depth, and tweaking brass, slight neck tension adj, your rifle will not only group tightly at 500, but your numbers will be sweet, it's like clockwork. I myself will not develop on more than 1/2" of vertical dispersion, 1/2" at 500 will be 2 1/2" or greater at 1K, and by 1200 will be over 8", I do this on non windy days just for clarification.
Just going off chrono numbers is a total waste, now I wish I had taken a pic of my magneto screen last week, 110 sierra, 6 creed, I had unreal numbers at 3157fps range, 5 shots, ES of 3, SD of less than 1, but it shot 2moa at 500, worthless, got it down to 3110fps range, 3/8"group.
Sometimes in load development, you have to pay your dues, the more you realize things, the less barrel life you're going to waste finding a load.
 
Just speculating here, but I think a lot of what you're reading is getting lost in the translation, everyone seems to want to post their new and improved method of finding the perfect load. I believe in the OCW test, and run a combo of a ladder and ocw at 500 yards, I also believe in the barrel time theory, but here is an area we cannot truly measure and must rely on a program like Quickload for assumptions.
Here's the deal, you say you shot 45 rds over your labradar, most likely at 100 yards waiting for magical numbers to transpire. If you were to get the components, brass, bullet, primer, powder charge, etc.. to get into a pressure range that your barreled action likes, the numbers tighten on their own. Get a larger pc of steel, set at 500 yards, draw a level line across it, then mark some aiming points, then load 3 charges each of varying weights in succession, set the LR up, and shoot 2 of each, the 3rd for a called biff. When you see 2, or more favorably 3 charges that hold vertical at that distance, scroll back through LR and you will see tighter numbers. Realistically, now picking a charge in the middle of this will work, but now, adjusting seat depth, and tweaking brass, slight neck tension adj, your rifle will not only group tightly at 500, but your numbers will be sweet, it's like clockwork. I myself will not develop on more than 1/2" of vertical dispersion, 1/2" at 500 will be 2 1/2" or greater at 1K, and by 1200 will be over 8", I do this on non windy days just for clarification.
Just going off chrono numbers is a total waste, now I wish I had taken a pic of my magneto screen last week, 110 sierra, 6 creed, I had unreal numbers at 3157fps range, 5 shots, ES of 3, SD of less than 1, but it shot 2moa at 500, worthless, got it down to 3110fps range, 3/8"group.
Sometimes in load development, you have to pay your dues, the more you realize things, the less barrel life you're going to waste finding a load.

This is funny because this is exactly the direction the discussion in Canada went. Some guys advocating only looking at the targets and others going a different/combined direction (myself included).

Actually, I was doing my final step of load development at distance (300M and 500M) which is what my range goes to. I have easy access to a 100M range and start my load development there. I look for a load that groups well and has a good ES/SD. When I have time I go to my clubs other range that has more distance and make sure things check out. When I did my development for my 6.5X47 I had a similar experience to you - a load with insane SD/ES but it wouldn't group below .75. My final load had a higher SD/ES but shoots very well.

With my methodology I put together a 10 rd group at 300M that was 1.7" CTC (which is .5XXMOA ) off an Atlas and squeeze bag and a .7 MOA 10 round group at 500M but I didn't have an aiming point aside from centre of the paper.

I am someone who does not spend a lot of time on load development though. I look for something that will shoot 1/2 minute and call it a day. At matches I will much more likely lose the match due to a bad wind call than a load that shoots 1/2 minute versus 1/4 minute.

I was just simply trying to say that pics of your chrony with an SD of 5 are kind of useless when your sample size is 5.

Edited to add:
If I was an F-Class shooter I would be a lot more concerned about things but there are very few sub 1 minute targets at the matches out there - or at least the ones I shoot.
 
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I'd be okay with it if everything else behaved.

I do a single load dev at 300-500yd looking only for vertical dispersion on a 24x24" plate. I compare POA vs POI on the various loads so it's probably really similar to Milo, combo OCW/ladder. It's usually sinusoidal in terms of dispersion, so I pick the middle of the charge range that's tight/close to one another. After that I shoot 10-20 over a magnetospeed to get ES/SD numbers and a solid average. I mostly look at SD and to be honest I'd only start worrying if it was over 12.

Admittedly, I'm lazy and I don't care if I could shoot 1/4 MOA. 1/2 MOA is good enough for me and all the targets I shoot at. My (in)ability to read wind accounts for many times more misses than my range/dope errors, which count for many times more misses than pure dispersion issues.
 
Lots of good information since I read this thread last. I ended up using the same load but switching to CCI BR2 primers and that dropped my es/sd to 25/7.9
I will shoot them at 300 yards and see what I get for vertical spread.
edit: I was using Fed 210M
 
Lots of good information since I read this thread last. I ended up using the same load but switching to CCI BR2 primers and that dropped my es/sd to 25/7.9
I will shoot them at 300 yards and see what I get for vertical spread.
edit: I was using Fed 210M

There is still an easier way, a primer may fine tune your load some, it is your charge weight producing higher numbers.
 
Admittedly, I'm lazy and I don't care if I could shoot 1/4 MOA. 1/2 MOA is good enough for me and all the targets I shoot at. My (in)ability to read wind accounts for many times more misses than my range/dope errors, which count for many times more misses than pure dispersion issues.

I fully understand your reasoning, not saying I agree with it. 8 out of 10 times the diff between a 1/4 moa and 1/2moa is 20 bullets and a seat depth tweak once a load is suitable. I guess I would never shoot a load that could not repeat itself. If you go prone, center punch a 20" target at 1K, then follow it up with another and it hits 6-10" away from the first shot w/o any noticeable changes in conditions, there was no reason to be in the ball game to start with.
 
You're probably right. I have never played with seating depth changes, and never (felt I needed to) chased lands.

I do notice elevation spread opens up after 800yd or so a little bit, but still well within 90% of the steel I shoot at. I think the last time I remember shooting at something and cussing elevation spread was a 12x12" plate at 1678yd. I shot 15 rounds, hit 2 or 3, and missed by elevation (just high or low) maybe 2-3 others. The rest was windage, and I'm honestly not at the level where 1500+yd is anything but a guess for wind.

More realistic ranges, 600-1200yd, it's wind that bones me, elevation spread is well within the target. Under 600 I'm fairly dangerous lol...
 
While your numbers are not the best, they are NOT that bad. I would suggest getting a ballistics calculator, apps are cheap, and start plugging in the numbers yourself to see where you're at. I ran your information using a 6.5 Creedmoor shooting a 140 ELD-M at 1000 yards through a program and here's what I got using a DA of 2250:

2801fps - 287.1 inches of drop requiring 8.0 MIL of Up elevation
2834 fps - 278.9 inches of drop requiring 7.7 MIL of Up elevation

Now the thing to remember is these numbers are the EXTREMES of your ES window. Extreme in velocity spread is 33, extreme in elevation drop is 8.2" and difference in Up elevation is 0.3 MIL.This means that using your average, you'd get 2818 fps - 282.9 inches of drop requiring 7.9 MIL of elevation. The simple numbers are that you could expect impacts to be within 4.1" high OR low of your POA.

Now, it would be nice if the numbers were better but these will get you out there until your reloading skills and process for load development improve. Also, ask yourself if you can shoot this difference at 1000 yards. As for the Chargemaster, I've loaded and tested several different loads through mine and every one has had ESs of under 20 and SDs under 8. These numbers were gotten AFTER I started using David Moore's sleeve and insert. Before using them, loads and numbers were sporadic.
 
While your numbers are not the best, they are NOT that bad. I would suggest getting a ballistics calculator, apps are cheap, and start plugging in the numbers yourself to see where you're at. I ran your information using a 6.5 Creedmoor shooting a 140 ELD-M at 1000 yards through a program and here's what I got using a DA of 2250:

2801fps - 287.1 inches of drop requiring 8.0 MIL of Up elevation
2834 fps - 278.9 inches of drop requiring 7.7 MIL of Up elevation

Now the thing to remember is these numbers are the EXTREMES of your ES window. Extreme in velocity spread is 33, extreme in elevation drop is 8.2" and difference in Up elevation is 0.3 MIL.This means that using your average, you'd get 2818 fps - 282.9 inches of drop requiring 7.9 MIL of elevation. The simple numbers are that you could expect impacts to be within 4.1" high OR low of your POA.

Now, it would be nice if the numbers were better but these will get you out there until your reloading skills and process for load development improve. Also, ask yourself if you can shoot this difference at 1000 yards. As for the Chargemaster, I've loaded and tested several different loads through mine and every one has had ESs of under 20 and SDs under 8. These numbers were gotten AFTER I started using David Moore's sleeve and insert. Before using them, loads and numbers were sporadic.

Thanks for the input. I did update the thread a couple of posts back. I switched to CCI BR2 primers and my es/sd went to 25/7.9 which is better obviously. I'd like to see the es down to 20 or less but I'm happy. Seems like the groups with the CCI load at 100 yards may have opened up slightly compared to the FGMM 210m but it could just be my shooting. Still 1/2" groups with the CCI's. Just got a nice 1/4" group out of the federals but that could've been blind luck. I need to take it out to distance and see how the vertical is. Fire danger is high here and they've closed the long distance range here so all I can do is shoot it at 300 yards and see. I will be using in matches on steel though.
 
Now that I type out the velocitynunbers if that 2801 and 2808 weren't in there the numbers get a lot better. Es would only be 22 if I took those two shots out

If those two low numbers are extraordinary than it is okay. But you need to determine that first. If they are occurring because of your reloading process than they are not extraordinary and should be left in. Just an example.
 
Thanks for the input. I did update the thread a couple of posts back. I switched to CCI BR2 primers and my es/sd went to 25/7.9 which is better obviously. I'd like to see the es down to 20 or less but I'm happy. Seems like the groups with the CCI load at 100 yards may have opened up slightly compared to the FGMM 210m but it could just be my shooting. Still 1/2" groups with the CCI's. Just got a nice 1/4" group out of the federals but that could've been blind luck. I need to take it out to distance and see how the vertical is. Fire danger is high here and they've closed the long distance range here so all I can do is shoot it at 300 yards and see. I will be using in matches on steel though.

That is a good set of numbers. You can get them lower and if you shoot better then the rifle you might see a difference.