Fixing high ES

[TackDriver284]

When testing @ 100 using the .308 and 168 SMK / Varget. I used 43.8 grains at 2740 fps average, used a P35 and I am seeing ES of around 25 to 30 fps and I don't like it and knew what will happen at 600 yards. @ 100 yards it shoots .1 to .2 MOA which is nice, but,,,,I won't use it beyond 600 yards.
Tested @ 600 yards, and vertical is about 4.5 inches and an inch wide and I want to fix it, so I went home and tried different primers, BR2 which I'm using, CCI200 and FGM 210 and tested again @ 100 for ES, and same variation of 25-30 fps.
I switched to Hornady 168 BTHP and I'm getting the same 25-30 fps variation.
I'm using .001" neck tension, cases are fired 2 X, annealed until it barely glows under no lights and pull out of the flame, powder is weighed by the kernel, I bumped shoulders .002" using a bushing die, seated .030" off. | I can't think of anything I can do to fix this high ES.

I could guess maybe change the neck tension to .002" or change powder to IMR 4064. But damn, Varget is a fine powder for the .308 and I want single digits.
My 6 BR ( Varget ) and 6.5 Creed ( H4350 ) has 3 to 4 ES that I'm happy with. But not the .308

What do you guys recommend I do to get my high ES fixed?

 

[RL338]

Sounds like you’re doing the rights steps of solving your issue.
First is this brass all from the same lot?
Annealing is being done , good
Neck tension I use is 0.0015”
Crimping on my 7400 made a difference , no so on the Vanguard.
The last thing you can look at is neck thickness , might need to try a 80% clean up on them.

 

[TackDriver284]

Sounds like you’re doing the rights steps of solving your issue.
First is this brass all from the same lot?
Annealing is being done , good
Neck tension I use is 0.0015”
Crimping on my 7400 made a difference , no so on the Vanguard.
The last thing you can look at is neck thickness , might need to try a 80% clean up on them.

Yes, brass is from the same lot.
I had a .336 bushing in the die, and put in a .335 bushing, to increase tension, hope that helps it.
I size about 80% of the necks only, I leave the other 20% on the lower neck to center itself when chambering, always have done this.
Thinking of any other variables.

 

[xphunter]

You can try another powder for sure, but I would play with neck tension more now...sometimes heavier is better.
Is this a tight neck chamber?

 

[TackDriver284]

You can try another powder for sure, but I would play with neck tension more now...sometimes heavier is better.
Is this a tight neck chamber?

No, its not, its a SAMMI chamber.

 

[hunter24605]

I can’t prove it, because I ready don’t shoot long distances, but the hammer guys swear a light crimp with the Lee FCD will bring those numbers down, provided all things else are equal: brass, trim, neck, BTO, etc. I do know the using the FCD certainly doesn’t negatively affect anything.

 

[RL338]

I size about 80% of the necks only, I leave the other 20%

Sorry , what I meant was to turn the necks for clean up to eliminate neck thickness as a variable.

 

[300WSM]

When testing @ 100 using the .308 and 168 SMK / Varget. I used 43.8 grains at 2740 fps average, used a P35 and I am seeing ES of around 25 to 30 fps and I don't like it and knew what will happen at 600 yards. @ 100 yards it shoots .1 to .2 MOA which is nice, but,,,,I won't use it beyond 600 yards.
Tested @ 600 yards, and vertical is about 4.5 inches and an inch wide and I want to fix it, so I went home and tried different primers, BR2 which I'm using, CCI200 and FGM 210 and tested again @ 100 for ES, and same variation of 25-30 fps.
I switched to Hornady 168 BTHP and I'm getting the same 25-30 fps variation.
I'm using .001" neck tension, cases are fired 2 X, annealed until it barely glows under no lights and pull out of the flame, powder is weighed by the kernel, I bumped shoulders .002" using a bushing die, seated .030" off. | I can't think of anything I can do to fix this high ES.

I could guess maybe change the neck tension to .002" or change powder to IMR 4064. But damn, Varget is a fine powder for the .308 and I want single digits.
My 6 BR ( Varget ) and 6.5 Creed ( H4350 ) has 3 to 4 ES that I'm happy with. But not the .308

What do you guys recommend I do to get my high ES fixed?

When did you test your 6br and 6.5 Trendmore..cough cough "creed" ?

In other words did you test your 308...then shoot the others same time or even afterward?

You're trying to eliminate possible intangibles...but one could possibly be your Chronograph which would lead you down a rabbit hole.

Consistency is everything in reloading and you seem like you've a lot of experience with such....

My thought is you need to play around with your seating depth but before you do that there’s simple things to eliminate or verify....

#1
make sure your chronograph isn't the problem which can also have its own intangibles like battery, lighting etc...
A simple verification whilst shooting the 308 is shoot one of your other rifles with single digit ES and make sure it still is reading single digit ES from one of those during the same outing.

#2 How is your scale?
Electronics can be finicky. I've an RCBS scale that was spot on and worked great for years then all of a sudden it started reading sporadic. I'd calibrate it...didn't matter.
What I found was the port for the power jack was loose and if the 90° plug wasn't properly placed at 12:00 it was giving inconsistent readings. (Ball powder from a thrower using another scale to reference consistency. )
That led me to finding the port problem.
Had I been using extruded powder and ONLY the RCBS throwing below my target charge weight and trickle the rest in I would've been at (x.y) powder charge but a superficial charge that wasn't truly (x.y) as the scale was being distorted by the power port.

#3
Is there any step in your load make-up you didn’t do with the 308 that you did with your other two platforms of reference?

#4
Are you shooting factory seconds?

If so are you running your bullets through a comparator? I can tell you the words from a Sierra bullet technician. I asked one time if factory seconds are worthy of 600 yards (i shoot in 600 yard matches)
His reply was they can be but you need to run them through a comparator and sort accordingly.
He was also a competitive shooter and had used seconds himself.

#5
If the above intangibles check out ok then I'd say you need to play around with your COAL.
If that doesn't change anything...

#6
Try a different powder. You don't need to shoot it at 600 yards but rather just testing your ES. Perhaps that specific rifle just doesn't like Varget or YOUR varget.

It won't be the first rifle in the world that didn't like a specific powder

 

[xphunter]

I would still shoot at 600 yards in great condition, like you did last time

 

[TackDriver284]

Sorry , what I meant was to turn the necks for clean up to eliminate neck thickness as a variable.

Yes, I understood you on the last post, sorry I got you confused with my response. Yes, I have a K&M neck turning tool, it will be my last resort because it will affect my neck tension, I may have to buy a smaller bushing if i wanted to clean up high spots that may take .001" off neck thickness.

 

[TackDriver284]

When did you test your 6br and 6.5 Trendmore..cough cough "creed" ?

Gosh, those questions, I'll answer it to the best of my ability.

#1
make sure your chronograph isn't the problem which can also have its own intangibles like battery, lighting etc...
A simple verification whilst shooting the 308 is shoot one of your other rifles with single digit ES and make sure it still is reading single digit ES from one of those during the same outing. All three rifles was tested on the same day, other two rifles are still recording the same speeds / low ES

#2 How is your scale?
Electronics can be finicky. I've an RCBS scale that was spot on and worked great for years then all of a sudden it started reading sporadic. I'd calibrate it...didn't matter.
What I found was the port for the power jack was loose and if the 90° plug wasn't properly placed at 12:00 it was giving inconsistent readings. (Ball powder from a thrower using another scale to reference consistency. )
That led me to finding the port problem.
Had I been using extruded powder and ONLY the RCBS throwing below my target charge weight and trickle the rest in I would've been at (x.y) powder charge but a superficial charge that wasn't truly (x.y) as the scale was being distorted by the power port. I use a ChargeMaster first, then finish off with a FX120i. I weigh by the kernel which is .02 grains. So the problem is not my scales.

#3
Is there any step in your load make-up you didn’t do with the 308 that you did with your other two platforms of reference? Everything I do with all my other riffles as for case prepping, weigh, anneal, etc is exactly what I do for the .308, nothing different.

#4
Are you shooting factory seconds? Never used factory 2nds, always the good premium stuff.

If so are you running your bullets through a comparator? I can tell you the words from a Sierra bullet technician. I asked one time if factory seconds are worthy of 600 yards (i shoot in 600 yard matches) I use the Lock n Load comparator tools, same for headspace.
His reply was they can be but you need to run them through a comparator and sort accordingly.
He was also a competitive shooter and had used seconds himself.

#5
If the above intangibles check out ok then I'd say you need to play around with your COAL.
If that doesn't change anything...

#6
Try a different powder. You don't need to shoot it at 600 yards but rather just testing your ES. Perhaps that specific rifle just doesn't like Varget or YOUR varget. I have two lbs of IMR 4064, to try soon, but I'm not done with Varget. I'm working on neck tension right now. Changing from .001 to .002 tension.

It won't be the first rifle in the world that didn't like a specific powder

 

[jimbires]

Mark , a couple things I'd try before getting all crazy about things .

neck tension , I'd try increasing it . I've read as much as .005 . after this I'm thinking the neck tension probably stays the same .

do you dry lube inside the neck before seating the bullet ? if yes , try seating them dry .

 

[TackDriver284]

Mark , a couple things I'd try before getting all crazy about things .

neck tension , I'd try increasing it . I've read as much as .005 . after this I'm thinking the neck tension probably stays the same .

do you dry lube inside the neck before seating the bullet ? if yes , try seating them dry .

No, I never lube the insides of the necks before seating bullets, its always dry and clean.

 

[300WSM]

So you've ruled out equipment.
How soon do you need to shoot 600?

How did you come up with seating .030 off?

 

[xphunter]

If you do decide to clean up the necks, just know you won't have to go full clean to do the job.
If the neck cleans up around 75% that is good enough, especially since it is not a tight neck chamber to begin with.
Take a sample of 5-7 cases to get the right setting

 

[RL338]

It’s hard to believe that your combo is mistreating you.
308 Win. , Lapua brass , 168gr SMK , and Varget you can’t combine a better load.

 

[TackDriver284]

It’s hard to believe that your combo is mistreating you.
308 Win. , Lapua brass , 168gr SMK , and Varget you can’t combine a better load.

That is true, its a great combo.

 

[xphunter]

If you get stuck, I have some 180 grain JLK long tails you can try

 

[TackDriver284]

If you get stuck, I have some 180 grain JLK long tails you can try

I have never tried JLK bullets, but I have heard of them. I have a 11:25 twist, and I have used up to 178 grains in ELD M and X. Never tried the 180's and over. They were deadly on deer, easy bang flop each time.

 

[300WSM]

View attachment 19421
I have never tried JLK bullets, but I have heard of them. I have a 11:25 twist, and I have used up to 178 grains in ELD M and X. Never tried the 180's and over. They were deadly on deer, easy bang flop each time.

It may have got lost as you've a ton of what if replies here...

But I'm curious as to how you came up with seating .030 off.

Unless I missed it you've mentioned nothing about your seating depth minus seating it .030 below and that was what...
Again...perhaps I missed something