ES vs accuracy

Idaho Hunter1

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May 5, 2019
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Boise, ID
What are you using to throw and weight powder. Back in my chargemaster days I could never get super low ES. Since then I have been running fx120i and running expander mandrels and I can keep my SDs in low single digits. I use a chargemaster now to do initial throw and trickle up with dandy trickler on Fx120i. I think I solved my two biggest factors that affect ES and that was powder charge consistency and neck tension.
What function did the expander mandrel perform in lowering the SD? Thanks
 

nt7332

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Nov 24, 2016
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With annealed brass opened all of necks to exact same diamater. And best part is it opens from top to bottom unlike expanders in dies which opens from bottom to top which can introduce run out. I have had great results with the mandrels. It right, wrong or indifferent just my way. Thanks brother
 

Beluebow

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Ar.
How low does your ES have to be before you can shoot a small group....say at 1000yrds? I'd like to know this number because I have never seen it posted.....asking for a friend. 😅😅
 

Jumpalot

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Full disclosure from a personal experience. I had a 7mm RM built by earlier said gunsmith. It was giving me fits. No idea why, but with a 180 Berger and H1000 I had a load that was an ES of 7. Couldn't make it hold a group better then a paper plate at 600 but would shoot 1/2" at 100. I switched to 168 Bergers with H4831. ES was 16 but would do half MOA at 600 pretty consistent. But it bugged the crap out of me that my ES was double the ES of the other load. Spent some time talking with the gunsmith and then he asked me why I was chasing ES. 600 Yds is what I had built the rifle for as it was a sub 7lb rifle and I had other rifles to shoot farther. I did kill a deer at 1056yds with it on a perfect condition morning cold bore shot. I know there were other variables then just the ES. I also decided that with all the info out there from this forum as well as others I could find a pretty good idea where velocity was going to be to put into the ballistic calculator. After a group at 750-800yds I could tweak my velocity in the calculator pretty darn close. Shoot a couple more groups at 500 and a couple more pushing 1000 and drop charts were pretty much verified. So, I got rid of the chronograph. The one time I couldn't get it to match was because the BC for 300 grain Berger was wrong. I also don't sort brass. I will shoot a lot, if I get a weird flyer, I'll mark that case and load again. If it is a flyer again it gets tossed out. I cull arrows the same way. Love this forum to learn and try new things. I have a buddy who doesn't hunt, just shoots for fun and is trying to learn the long distance game. His shooting range goes to 600. I'm teaching him to do all the things I don't do so he can learn for himself what makes a difference and what doesn't for him. He's turning necks and keeping data. So far not much difference as he's already starting with good brass, but now he knows. He's weighing and sorting brass and comparing loads, so far not enough difference at 600yds. He's tried to run ladders and ended up more confused then when he started. He's bought the Applied Ballistics book and read it. He'll call me up and talk to me and I always tell him to go try it so he knows. What he's learning(it took a couple of years, while I waited patiently for him to get there) is that he is the biggest variable. I told him in order to overcome that, he needs a lot more trigger time. Bryan Litz said it best, if your missing because of reasons that aren't ES then reducing ES isn't going to fix it. Love this thread, hope the OP finds the magic load and goes and shoots his barrel out so he can start over and learn more.
 

Alex Wheeler

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Jul 5, 2017
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Montana
Dont worry about ES if its around 20 or better. It is routine for sub 3" groups at 1k to have 15-20 fps of ES. Very rarely do the really small ES groups shoot best. Its something I have watched for years now in 1K BR tuning and its an odd thing, but it is so consistent there is definitely something going on there. Unless you can take that rifle to 800 and see how it groups, you wont really know what its going to do.
 

Beluebow

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Ar.
Dont worry about ES if its around 20 or better. It is routine for sub 3" groups at 1k to have 15-20 fps of ES. Very rarely do the really small ES groups shoot best. Its something I have watched for years now in 1K BR tuning and its an odd thing, but it is so consistent there is definitely something going on there. Unless you can take that rifle to 800 and see how it groups, you wont really know what its going to do.
Well that's gonna spoil the fun for a lot of folks!! Couldn't agree more! 😂👍
 

nt7332

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Well that’s cool if u want to load 15-20 ES. I load because I don’t want that. Glad it works out for u, however, I will continue to strive for below 10. To each their own and what they choose to spend their money on.
 

MTbackwoods

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Mar 5, 2020
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Montana
Yeah it’s odd that way more often than not, my low ES groups aren’t the best. But I hand load to strive for perfection and just reduce variables. ES isn’t the most important thing because numbers are always subject to change. And I’m hoping to shoot out the barrel soon so I can rebarrel any way. I’m trying every powder and bullet combo I can convince my fiancé to let me buy just so I can get more experience loading and kill this barrel 😁. My plan is to build affordable precision rifles some day soon so I have a hunger for knowledge when it comes to this stuff. But I appreciate everyone’s time and input. I’ll definitely post results after I get back out and shoot at distance this weekend
 

LongBomber

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Dec 27, 2008
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Fernie BC, Canada
I wouldn’t be too excited about es over only a couple shots. Over only a couple shots It can tell you if it is really bad - like you see a 50fps spread in 3 shots. But if you have an es of say 10 over 3 shots it may not be telling you the truth, you shoot that same load in a ten shot group and surprise it has en es of over 25 and an sd of 15.
After tracking a couple rifles over 50-100 rounds each, I would say an es of under 20 for 20 shots is pretty solid.
 

xkiwiculler

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Mar 30, 2014
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Hi i have been watch this conversation and i cant figure out what "es" is, I must say i dont reload but would love to know what it means.
 

xkiwiculler

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Mar 30, 2014
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Hi thanks for the fast reply Unoboats, I am just starting into long range hunting at the young age of 74. I was a professional culler in the early sixties but nothing beyond 400yds. straight barrels
 

codyadams

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Southwest Wyoming
Well that’s cool if u want to load 15-20 ES. I load because I don’t want that. Glad it works out for u, however, I will continue to strive for below 10. To each their own and what they choose to spend their money on.
I would venture to say that Alex Wheeler has likely forgotten more about precision long range shooting and rifles than most of us know. He is a solid resource for excellent information. Not saying it's bad to have very low e.s., but Alex knows very well what he is talking about as well.

3 shots tells you very little on e.s., I prefer to find a good seating depth, then find my max load while checking speed, then do a ladder test at 600+ yards, preferably through a flat spot from my velocity testing. The results at range tell me what I need to know about my velocity. After I find my final load, I shoot 10 rounds over the chornograph to get some solid numbers on my average velocity to put in my ballistics app. If my ladder test doesn't show me the results I want, or if my initial pressure test is all over the place with no consistency or flat spots, I usually try changing primers to get better results. My .260 AI with BR-4 primers and rl26 worked great with the 147 eld-m, however with the 156 eol, it had 50+ fps e.s., switched to the cci 450's and brought it down to high teens.

At this point, I would just run a ladder test in your situation, unless you already have what you would consider acceptable long range performance.
 
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