How to fix ES issues

[yourcfi]

I have noticed that I am having trouble trying to tighten up my ES.

Here is what I got

300WM rem 700 190 & 210 VLD h-1000 81.0 77.5 fed 215 0.005-0.020 off

ES is not bad but I cannot get it any tighter than about 40-50

Any helpful hints?

 

[stockdoc]

Re: How to fix ES issues

First off, how are you dispensing powder? are you making sure every charge is EXACTLY the same as the last? consistent powder charges will really help your ES in the long run.

Second, 005-020 off? What are you using to measure this? bullet tip? ogive? Different bullet jumps will give you different pressures for each shot thereby affecting your ES. Bullet tip measuring is very unreliable since all bullet tips are not the same, so you will get different measurements. A tool that measures to the ogive is much more reliable and repeatable.

Third, why 215 primers? are you shooting in freezing conditions? The standard 210 or 210M primer has a very consistent flame which will give you very consistent powder burn characteristics and that will lower your ES as well. Magnum primers have a very violent flame which can ignite the powder unevenly causing high ES.

Fourth, are your primer flash holes reamed from the inside? Primer flash holes are punched into brass and that leaves a very uneven jagged surface for the primer flame to come through. Reamed flash holes allow the primer flame to come through evenly and burn the powder more consistently which will also affect ES. This is an operation done only once, when you first get new brass, or once fired factory brass. It is easy to accomplish and doesnt take very long either. All the major reloading companies offer a tool to accomplish this task.

Fifth, why VLD bullets? have you tried Sierra 190/210 SMK? VLD bullets are notorious for being picky about jump into the lands. The Sierras are very forgiving of jump and tend to shoot well without a lot of work. Not saying the VLD's are bad bullets, they just require a little more effort to make them shoot well.

All these items are cumulative and will affect the ES of your loads. By performing all these steps my 300 WM loads have SD of 12 or so and my ES is 6. I hope this helps. Good luck

 

[Paladin2147]

Re: How to fix ES issues

What does the target look like?

 

[CanSniper]

Re: How to fix ES issues

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: kolkio</div><div class="ubbcode-body">What does the target look like? </div></div>
Pretty sure I know where he is going here, I spent a lot of time and money chasing ES, when most of my prob was a crappy chrono.
The Target tells the truth.

 

[yourcfi]

Re: How to fix ES issues

I learn something new everytime...

I will try some of my 210M's for starters.

Brass has been uniformed and weighed all within 2 grains

My VLD's are grooping well out to 600ish yards, 1/2 MOA give or take, by 1000 my windage is consistent enought for me, but my vertical is up and down by +/- 2 feet.

I have questioned to chrono before but on the 308 it is reading great, ES between 6 and 18 on two different loads.

Do standard lee seating dies seat propertly off the ogive on VLD's?

 

[gvanhyning]

Re: How to fix ES issues

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MNS</div><div class="ubbcode-body">I learn something new everytime...

I will try some of my 210M's for starters.

Brass has been uniformed and weighed all within 2 grains

My VLD's are grooping well out to 600ish yards, 1/2 MOA give or take, by 1000 my windage is consistent enought for me, but my vertical is up and down by +/- 2 feet.

I have questioned to chrono before but on the 308 it is reading great, ES between 6 and 18 on two different loads.

Do standard lee seating dies seat propertly off the ogive on VLD's? </div></div>
The +/- 2 feet is a reflection of the ES.

 

[308sako]

Re: How to fix ES issues

I disagree with the Federal 215 M's being a problem with a charge weight of nearly 80 grains of such a slow burning rate powder. But try the Federal 210 M's and see what your rifle likes! You might also be well advised to try a different brand of primers, like the Wolf or Tula large rifle magnum primers. In my .308 Rock Creek they are the best performer for low SD's and tight ES. Oh, yes that is magnum large rifle in the .308...

Uniformity of neck tension as well as seating depth is a major factor, but what is the charge density or fill in the case?

My 2 cents

 

[Paladin2147]

Re: How to fix ES issues

The only numbers that matter are on/at the target. That's "The Test". Not all the work up. If there is a issue, then look at the work up. There are many reasons chronos give false readings.

But remember - Don't argue with the target.

 

[yourcfi]

Re: How to fix ES issues

Density is full or near full.

I will try a bunch of primers and see if I get any changes.

Any tricks to get uniform neck tension?

 

[yourcfi]

Re: How to fix ES issues

I would like to try the SMK's but I need a hunting bullet. I am open to ideas...

 

[Goldbeachman]

Re: How to fix ES issues

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: stockdoc</div><div class="ubbcode-body"> By performing all these steps my 300 WM loads have SD of 12 or so and my ES is 6.

</div></div>

Maybe these numbers were meant to be reversed?

 

[yourcfi]

Re: How to fix ES issues

reversed would make more sense.

 

[stockdoc]

Re: How to fix ES issues

goldbeach and mns, you are correct, I reversed those numbers by mistake.

308sako, I had a 338 rum that burned 86.5 grains of rl-22 with standard 210M's. Never an issue and, dont have my notes handy, but the es and sd were very low on it as well. The magnum primers might be an issue in colder climates, but in my ao they are not needed.

MNS states he's +/- 2 FEET VERTICAL on target so it clearly is not just a chrony issue

 

[Deadshot2]

Re: How to fix ES issues

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 308sako</div><div class="ubbcode-body">

Uniformity of neck tension as well as seating depth is a major factor, but what is the charge density or fill in the case?

My 2 cents


</div></div>

Definitely pay attention to neck tension uniformity.

I had some new brass that yielded some great performance. After a while my groups started opening up with the same EXACT charges. All charges were dispensed from a Chargemaster thus every charge was weighed rather than every 10 or so.

I recently annealed all the cases that used to perform so well. I then F/L sized the cases with the depriming rod/expander ball removed. (I deprime with a universal die after shooting sessions so I can clean brass in Stainless Pin tumbling media and have TOTALLY clean cases). After sizing, I then use a Sinclair Expander Die with the O/S mandrel. The combination of annealing and expanding with the Sinclair die has yielded very uniform neck tensions and the performance is back where it started out.

As you size brass with a conventional sizing die that pulls a ball back through the neck, uneven brass thickness, consistency of the metal, and work hardening, can cause the neck to both be somewhat crooked and also spring back at different rates.

Annealing solves the work hardening variations.

Neck Turning removes most of the consistency/thickness issues.

Expanding with a mandrel keeps the neck straight as it maintains full contact as it enters and is withdrawn, not like a ball expander that follows the line of least resistance.

YMMV but this process has worked great for me. I'm still using the same load, primer, and bullet, the improvement has come from the case processing.

 

[yourcfi]

Re: How to fix ES issues

i have annealed.

I will look closer at the neck tension and try crimping vs not crimping as well.

 

[308sako]

Re: How to fix ES issues

xxx

 

[JByrd]

Re: How to fix ES issues

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MNS</div><div class="ubbcode-body">i have annealed.

I will look closer at the neck tension and try crimping vs not crimping as well. </div></div>

no crimp.

 

[stockdoc]

Re: How to fix ES issues

+1000 on the no crimp statement

 

[jrob300]

Re: How to fix ES issues

Another factor that a lot of people miss with regard to consistency of velocity with a heavy recoiling rifle is the shooter.

Are you shooting from a bench or prone? If your position behind the rifle and the resulting pressure against the buttstock differs from shot to shot, you are inducing velocity variation.

If shooting from the bench use exactly the same shoulder pressure from shot to shot. I've found this more difficult than prone as I have to use my core muscles to lean into the rifle and it's more difficult for me to get consistency than when laying prone and simply raising my chest a bit and then leaning into the buttstock to load the bipod. Especially during long range sessions. With prone the only factor is loading the bipod the same with every shot.

Try an experiment. Chrono a shot with almost no shoulder pressure or free recoil. Note the velocity. Then chrono a shot where you grip the rifle firmly and put a lot of shoulder pressure resisting rearward movement. Note the difference. Also note that firmly gripping the rifle may not be best for ultimate accuracy. You have to find what works best for you... but consistency from shot to shot... not just in the ammo, but in your form, will pay dividends.

John

Edit: I just noticed the "1/2 moa at 600, +-2'(!) at 1000 yds." I'm having a really difficult time coming up with a scenario that could yield those kind of results unless something changed between the two distances.

 

[yourcfi]

Re: How to fix ES issues

For neck tension, how much should be used?

 

[Sportin Wood]

Re: How to fix ES issues

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MNS</div><div class="ubbcode-body">For neck tension, how much should be used? </div></div>

.002

 

[josephberry]

Re: How to fix ES issues

.001-.002 or whatever your rifle likes.

 

[Deadshot2]

Re: How to fix ES issues

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MNS</div><div class="ubbcode-body">For neck tension, how much should be used? </div></div>

Just enough to keep the bullet from falling out of the case if single loading or just enough to keep the bullet from moving while in the magazine under recoil.

You'd be amazed at how tight a bullet is held with only .001" of neck tension.

 

[yourcfi]

Re: How to fix ES issues

to be honest I don't even know where I am at right now. do you measure off the inside on the case neck or off the mandrel on the die?

 

[Goldbeachman]

Re: How to fix ES issues

To determine "neck tension" just measure the outside of the neck of the case before you seat the bullet and then again after. The difference is the "neck tension."

 

[Deadshot2]

Re: How to fix ES issues

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GOLDBEACHMAN</div><div class="ubbcode-body">To determine "neck tension" just measure the outside of the neck of the case before you seat the bullet and then again after. The difference is the "neck tension." </div></div>

And it's just about the only way to do so accurately without buying more expensive measuring equipment.