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?
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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?
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.
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
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.
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.
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
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.