Trouble shooting high ES

[MOShooter]

I'm working on loads for my 6slr and my ES is running in the low 40's. I'm using Hornady brass that was new and is now once fired. My go to load has been 43.8g of H4831. Now I'm working with H1000. I've found that 46.4g shoots very well. In prep for an upcoming match I sorted my brass by weight. I shot some today that all cases where within .5g and had my worst ES yet 61. All charges are weighed using my chargemaster. If there's a bright point this load still shot a 146 4x in 15 rounds today. So I'm open to any ideas on how to reduce my spread.

Scott

 

[JamesnTN]

Change primers for one and then if that doesn't help change powder. Once you've change enough components and still have a High ES buy a scale that will resolve 1/2 of what the chargemaster does. Other words find a scale that'll measure .02-.05 grains instead of .1 grains

 

[MOShooter]

Both H5831 and H1000 are both about the same. With the h1000 I've tried 210m and BR2. H4831 only 210m. I was thinking a new scale.

 

[JamesnTN]

IMR 7828 and RL22 would be another choice of powders to test. I do agree a better scale is always helpful.

 

[savagedasher]

I use a charge master . My ES is never more then 15. Case prep and the right primers is the answer
First primer pockets Annealing and Proper dies Last and the most important Internal case capacity
Weight of the case has no bearing on the internal case volume.
If one case the internal volume is 40 GR and another is 41 . The pressures will be different no matter how accurate you weigh the powder.
My cases I keep the internal volume in .002 together. The cases that have.006 difference shoot 20 fps different. I find in my dasher .002 difference of capacity is .001 difference in powder drop.
You can seperate the cases with a crony.. Fast ones in one pile and slow in another. If you use that method you will drop your SD & ES Larry

 

[Sniper338]

I agree with the above.... case prep does a lot..

 

[Patch700]

To echo slightly on what larry was talking about , i conducted a test on a set of brass that was wieght sorted.

I had grouped lots of brass that were withing .3 of each other as wieghed on an A&D Fx120i as well as the powder charges were kept within .01.

What i then did was run those batches over the chronograph and wrote in felt marker the velocity of each shot on that particular case..

Then I sorted the brass based on the written velocities.. Bingo , dropped the es down into the single digits as compared to what they were when they were merley wieght sorted ( es's were previously 20-28fps)

The first thing i noticed was there were quite a few cases that were within the same wieght catagory but had to be segregated into a completely different lot once compared to the velocities written on them.

Those same cases after bieng sorted by speed have since stayed in their corresponding lots as they seem to be consistent in their velocities still.

Good luck.

 

[MOShooter]

Thanks for the advise. Looks like I'm going to have to live with high ES. I'd have my barrel shot out by the time I got enough brass sorted of my needs. Not to mention I'd have to buy a 1000+ prices of brass. Lesson learned. Only use Lapua brass. Two guys I shoot with are running ES of about 10 with brass straight out of the box.

Scott

 

[lrgoodger]

I wrestled with the same problem. I finally got under 10 ES on the 6BRs when I started annealing and lubing the case necks with a Q-tip very lightly coated with Lee lube. It won't contaminate your powder and is easier to get a uniform coat on the inside of the neck than graphite. Weighing powder charge to the nearest kernel doesn't hurt anything either and I'm running .001 neck tension set with a Lee collet die and then expanded with a K&M 6mm expander. The bullets seat smooth as butter.

Still wrestling with the 284 Shehane ES (much larger volume case). I think sorting cases by velocity might be the answer. I'm going to try it. I just can't bring myself to volume sort by filling the case with water and weighing it.

 

[BountyHunter]

First off, what chrono are you using?

Many chronos are not real accurate and you could be the victim of a cheap chrono.

 

[MOShooter]

First off, what chrono are you using?

Many chronos are not real accurate and you could be the victim of a cheap chrono.

Magnetospeed sporter.

 

[Joe R]

Before somebody goes off the rails with the chronos, here's a comparison of the MagnetoSpeed and Oehler 35P data (see below).

Regarding the wide ES, there are way too many things that could cause that.

I use the ChargeMaster for my primary powder dump and then I finish it on a more accurate scale. The CM chronically under throw's powder. It is rare for it to over throw. It's off as much +/ 0.2. In my powder 0.1 of powder translates to 5 fps so +/- 0.2 could account for a 20 fps variance.

In my limited experience, I've only been intimate with two powders Varget and IMR 8208. Both shoot well and have lots of good characteristics one gives me lower SD's (1-4) and ES (5-12) and shoots quite well. The other is a bit more "spikey" and gives me slightly higher SD's ( 4-7) and ES (5-19) but on paper it produces better results. So which do I go with??? I decided that the target rules and the chrono is there for support and info. Don't put the chrono ahead of the target. It's easy to get confused and start using it as a crutch.

For me personally, I brought down my ES substantially when I got my neck tension problem resolved. Alas it took an Hydra press to make me realize that I did have a neck tension problem. Look at your reloading process, what can you measure and what you can't? If you can't measure it, well, you're guessing and chances are that's where your problem is. And after you can measure it, then the question will be: how accurately? .001 or .0001, etc....

Kindest regards,

Joe

 

[MOShooter]

I ordered a better scale. Going to start there and see if it makes much difference. I still think better brass would make a big difference.

Scott

 

[lrgoodger]

A better scale will only improve the situation, but the percentage of improvement may be so small as to be unnoticeable. Other factors constitute a much larger percentage of the ES issue.

 

[Joe R]

I ordered a better scale. Going to start there and see if it makes much difference. I still think better brass would make a big difference.

Scott

My experience contradicts your presumption. I've gone from Federal to Lapua to LC and in each case when in a head to head comparison (same velocity, different charge) I could not see the difference over 3 5-shot sgroups, but YMMV. I partially agree with:

LRGoodger
A better scale will only improve the situation, but the percentage of improvement may be so small as to be unnoticeable. Other factors constitute a much larger percentage of the ES issue.

As Erik Cortina once told me, the Holy Trinity of accuracy are 1) Powder 2) Neck Tension 3)Seating depth. I would look there first. A better scale will help with the powder aspect but you've got the other two to consider.

Kindest regards,

Joe

 

[dmoran]

A better scale will only improve the situation, but the percentage of improvement may be so small as to be unnoticeable. Other factors constitute a much larger percentage of the ES issue.

If one is on the center of a good accuracy node, and is shooting in an ambient that holds that node center, then I agree with you, and there is forgiveness to the powder tune and to the charge window. If the ambient or tune has it off sided, a precise charge window is much more significant. Having a precise scale, can illuminate charge error/variance from the equation all together - IMO
Donovan

 

[lrgoodger]

A better scale will only improve the situation, but the percentage of improvement may be so small as to be unnoticeable. Other factors constitute a much larger percentage of the ES issue.

If one is on the center of a good accuracy node, and is shooting in an ambient that holds that node center, then I agree with you, and there is forgiveness to the powder tune and to the charge window. If the ambient or tune has it off sided, a precise charge window is much more significant. Having a precise scale, can illuminate charge error/variance from the equation all together - IMO
Donovan

Staying in the center of an accuracy node and reducing ES are two separate issues. You can be in the center of the accuracy node and have a terrible ES. Conversely, you can have a great ES and be off the accuracy node. Both are important.

I agree that eliminating powder charge variance from the equation is an important step. That is why I started weighing to the nearest kernel quite some time ago. I'm just pointing out that I think he has bigger problems getting control of ES and not to expect too much effect on ES just from better weighing, although it is something he should do. Getting control of neck tension will have a much bigger effect on ES than increasing weighing accuracy from a tenth grain to a hundredth grain.

 

[rminut]

Scott,
what is the SD for the load?? That is a much better indicator of how the load is working or not. What was the SD/ES for the 4831 load? I am assuming that was using the same brass so a big change in numbers between powders would quickly indicate a powder/load issue.

it's interesting to see how many recommend buying a new scale when so little information was given. ES is only measuring TWO rounds so the SD could still be quit good, and just two pieces of brass have different neck thickness. You even said it shot well for score so that is showing you how little ES matters on the target, although you didn't mention what distance that score was shot at.

not trying to stop you from throwing money at the problem but many people make fantastic shooting ammo with a simple beam scale.

 

[bill123]

To echo slightly on what larry was talking about , i conducted a test on a set of brass that was wieght sorted.

I had grouped lots of brass that were withing .3 of each other as wieghed on an A&D Fx120i as well as the powder charges were kept within .01.

What i then did was run those batches over the chronograph and wrote in felt marker the velocity of each shot on that particular case..

Then I sorted the brass based on the written velocities.. Bingo , dropped the es down into the single digits as compared to what they were when they were merley wieght sorted ( es's were previously 20-28fps)

The first thing i noticed was there were quite a few cases that were within the same wieght catagory but had to be segregated into a completely different lot once compared to the velocities written on them.

Those same cases after bieng sorted by speed have since stayed in their corresponding lots as they seem to be consistent in their velocities still.

Good luck.

This sounds like a good idea but won't conditions from day to day prevent you from accurately sorting brass by MV? In other words, can cases shot on one day with a specific MV range be grouped with cases having the same MV range from another day?

 

[MOShooter]

I would have to set down and calculate my SD for the H4831 load. I've tested it twice and the ES was 36 & 41. The SD for the H1000 load was 20 and ES 61. Yes I've been using the same lot of brass. The score was shot at 600y. This all started as a quest to find more speed. The H1000 shot well enough in testing that I want to use it in the upcoming match at club. It shots well enough for banging steel in which it was built for. However, if I want to be competive in our monthly Fclass I think I need to do better.

At 600y what is considered acceptable accuracy? Maybe I'm getting worked up for nothing.

Scott