How to lower ES

[Vandy321]

300wm, berger 215s and GM215M primers...seems slot of folks are getting single digit ES with this combo.

I've chrono'd a few charge weights now and everything seems pretty steady at about 20, including the node I'm loading.

Getting 2981 fps, ES of 19-22 and an SD of 7-9.

I do the following to help ES, anything else?
Neck turned/clean up necks
Uniform primer pockets
Debur flash hole
Neck Bushing down and expand with mandrel to set tension
I dip the bullets in graphite powder (cases are steel media wet tumbled)

I try to seat my primers to a .002 crush, but that seems to very from flush to .004 crush...assuming that is not helping my cause. Do I need to pay attention to primer crush (or no crush) depth?

I'm going to try some CCI 250s as well, as some say it dropped ES in half when they switched, but that could go either way.

I'm probably missing stuff some. But I try to do it all.

What else have you found that helps improve ES?

 

[Wheres-Waldo]

How many rounds are you measuring in a string?

How are you measuring powder?

Try sorting some bullets by bearing surface.

Try sorting some cases by weight.

 

[Vandy321]

How many rounds are you measuring in a string?

How are you measuring powder?

Try sorting some bullets by bearing surface.

Try sorting some cases by weight.

5 shot strings

Measuring with a Dillon beam scale

Never heard of sorting by bearing surface?

I'l probably only sort cases by weight for my 8 rounds I take hunting.

I'm not super unhappy with a 20 ES, but it sure would be nice if I could half that.

 

[hafejd30]

Bullet sorting
Annealing if previously fired cases
Play with seating depth

I use rcbs chargemaster. For some of the really particular loads we run them past a jeweler scale as well

What are you using for brass?

 

[Vandy321]

ADG brass

How many groups are you guys sorting the bullets by...assuming you length to give? Sort them in each .001"?

That makes alot of sense and seems like an easy thing to do on the couch at night. Any details or techniques on that you could share?

All I have is a starret caliper and the hornady bullet comparator (sits on the Ogive) to mount on it. Assuming that will do the trip?

 

[Wheres-Waldo]

Case weight is partially indicative of internal volume, which will play a part in pressure. The same can be said for bullet bearing surface

+1 on annealing as well

 

[hafejd30]

Yes .001”

A comparator on each end is the best method for the bearing surface.

 

[Vandy321]

Weighing brass is going to be a pain in the ass on a beam scale. But may give that a go too...how picky are you on brass weight for sorting...every .1 gr?

 

[hafejd30]

I originally used Fed primers you mentioned above but got the same results you did. Switched to the CCI and got way better Es and sd. So yes that is a start.

Take the time to hand sort 5 bullets, 5 cases, make sure the powder measurement is exact etc and see if you notice any improvements.

I sorted 1000 Berger’s for my 284 and only found a small amount to be rejects. Most were within .003” of each other. Hornady on the other hand I’ve had as much as .017” difference in a single box of 100

 

[hafejd30]

Is this a factory rifle/barrel or custom?

 

[Vandy321]

Custom build

 

[918v]

What powder? H1000? Try 210’s.

 

[Vandy321]

What powder? H1000? Try 210’s.

I would, but it's a hunting rifle, really want the cold weather reliability of the magnum primer.

I know some say it doesnt matter, but I'd hate to ruin a hunt over it.

 

[Alabusa]

I am getting single digit es and sd with 190 VLDs in Nosler brass, H1000 and Winchester LRM primers. I am not sorting anything.

 

[Vandy321]

Sorting bullets right now. Going to load up 10 of each 215m, CCI 250 and Win LRMs. Shoot a 5 shot group and 5 over Chrono with each. Thanks for the pointers guys.

 

[hafejd30]

What crono are you using?

 

[Vandy321]

Mag speed...dont like how it shoots for groups with it on...

 

[hafejd30]

I have same. Mine actually seems to shoot just as good with it on as it does off. Zero sometimes changes. That said I also do the same as you and don’t test with it on.

My 284 shot a 1.25” 5 shot group at 500 with it on when I was testing mine

 

[918v]

I would, but it's a hunting rifle, really want the cold weather reliability of the magnum primer.

I know some say it doesnt matter, but I'd hate to ruin a hunt over it.

There is no cold weather reliability issue with 210’s in the cold.

 

[Browerka]

Have you tried messing with bullet tension? I use to use .002” on all cartridges, seems like some like a little tighter hug.

 

[Vandy321]

One string I had .0025 or so (assuming .0005 springback), other should have been .0015, no change in SD, so I'm going back to .0025. I have a .307 .306 and a .3055 expander. Have not used the .3055 yet. Assuming that would set about .003 with a .0005 springback.

 

[mahlv]

Seat your primer, then rotate the case in your priming tool 180deg and give it another ugga-dugga.

I tested this out, and reduced ES and SD by 1 on a load that was 16ES and 5SD. 5 shot strings, so could have had zero effect, but it’s easy enough to do so it’s now part of my routine

 

[Browerka]

One string I had .0025 or so (assuming .0005 springback), other should have been .0015, no change in SD, so I'm going back to .0025. I have a .307 .306 and a .3055 expander. Have not used the .3055 yet. Assuming that would set about .003 with a .0005 springback.

I have found in 2 different calibers they like .004 tension.

It can be frustrating i know, seems like you have gotten rid of all variables.

 

[918v]

Also try dry neck lube in the neck.

 

[Vandy321]

Also try dry neck lube in the neck.

I do, I dip the bullets in the Redding dry neck lube (graphite) as I'm seating

 

[Vandy321]

Sorted bullets, no real change in my 215m ES, but will continue to do it, too easy not too.

Did run 30 rounds over a chrono with 3 dif primers. 10 of each. Pretty crazy results.

Fed GM215s: ES 25, SD 9.8, Ave 2981
Win LRM: ES 41, SD 16.8, Ave 2996
CCI 250: ES 8, SD 3.6, Ave 2988

CCIs grouped at .66

Im not sure I can shoot this 300wm much better than .5, so im pretty happy. I think groups will tighten up a little more as I get better behind the rifle.

 

[wapiti16b]

How many rounds down this pipe so far?, I'm loading Berger 210gs until I run out of them and have treated all bullets with HBN . I do not weight sort the Bergers as they have been gtg so far. Fed magnum primers / H-1000 powder, Norma brass, all neck turned no weight sorting , uniformed primer pockets de-burred and neck turned. Neck tension 2thousandths graphite dipped for the necks not the bullets single digit SD so far with about 200 rounds down a new Broughton barrel 1n9 twist.
Round count matters so if you have a low round count be patient and go with your most consistent load. If you do not have a Larry Willis Collet Die get one ASAP! it will help with case uniformaty!

 

[hafejd30]

Looks like you found your source for Better es/sd Congratulations!!

Like I said I had similar results with federal primers as well. I bought several hundred. Most likely will give them away. CCI is my go to

 

[hafejd30]

At one point I tested them in a 308 I had. Tested the federal, CCI, win and Rem primers because I had them. Oddly enough the Remington primers shot the best. CCI next best.

Just 5 round groups at 300 yards.

That was over a $80 chrony which I had issued with. So I went by group size. I load tested with the federal and then compared them. If I do remember correctly the Remington were the slowest and Winchester were the fastest as far as velocity was concerned. When my chrono would pick them up

Was several years ago so I don’t recall the exact outcome. Just know my go to is CCI. I did run the remingtons for a bit in another 308 but had a couple primers misfire and just went to the CCI in that rifle as well

 

[Vandy321]

The 215s were holding good for 4 of each 5 shot group, but 1 would always throw the eS from a 10 or so to a 20+

Rifle has 180 rounds down the pipe.

 

[hafejd30]

The 215s were holding good for 4 of each 5 shot group, but 1 would always throw the eS from a 10 or so to a 20+

Rifle has 180 rounds down the pipe.

How many firings on this brass? And do you reload all the brass at once?

Just asking in regards to casings your using being fired more than others.

 

[Vandy321]

How many firings on this brass? And do you reload all the brass at once?

Just asking in regards to casings your using being fired more than others.

Same brass, all on their 4th firing, all loaded today.

 

[hafejd30]

?
Annealing the brass may help you out

 

[Baer45]

I think it is interesting that Black Hills uses (unless they stopped) solely Winchester primers for all their loads. They spare no expense so must have figured something out...

 

[Vandy321]

Thats my next step. I may ship them off as I'm not set up to do it at home. I've got a torch, but thats about it. I've got other brass that's once fired that I can run for a few trips while wait.

 

[Vandy321]

I think it is interesting that Black Hills uses (unless they stopped) solely Winchester primers for all their loads. They spare no expense so must have figured something out...

The win LRMs I had had very obvious vertical stinging on paper (even at 100), on both groups shot with them. Not present with the other primers and definately showed in the ES/SD...may have just had a wonky batch.

 

[hafejd30]

One more question;

Are you FL sizing or Neck sizing? I’ve found just bumping the shoulder was the most consistent vs just neck sizing. (For me that is) Admittedly I do both across a variety of rifles with great results from both

 

[Vandy321]

Neck sizing down with a .331 bushing after firing and setting final tension with a .306 mandrel.

Havent needed to bump shoulders, but will for next firing. Using a redding body die for that.

 

[hafejd30]

Anneal the brass
Bump the shoulder (.002”)

 

[Mr Flannel]

You might consider percentage of case fill you’re getting from your chosen powder/charge. I’ve found more variability in ES/SD where the case volume to fill ratio is lower. Not sure what powder you’re using but your cartridge might lend itself to trying a slower powder that fills more of the case capacity - but I’m not familiar with 300WM reloading, so I might be tilting at the wrong windmill.

 

[Vandy321]

Thanksx good point. I had someone run this load through quickload, I cant recall exactly, but it was right near 99-100% case capacity. 77.5gr of H1000 and seated .060 off gives just a slight crunch when seating, so I'm guessing that's correct.

 

[Mr Flannel]

Sounds like you’ve eliminated that variable. You might then consider that if you’re getting a slight ‘crunch’ to check your loaded round OALs after you’ve seated bullets and perhaps a couple of days after. If you’ve got a compressed load and reasonably light neck tension with necks that were lubed, you can get projectiles getting pushed back out slightly (and unevenly).

 

[Vandy321]

I will do that, thanks. I do measure each round CBTO after loading, it usually takes a small adjustment .001 down or so and a 2nd seating to get them perfect with the crunch.

I'm pretty happy with the CCIs ES/SD...if that stays consistent, at <10 ES, I'm done screwing with things.

 

[Mr Flannel]

To be honest, I think those numbers are pretty damned good - especially in a 300wm. Whatever you’re doing, it’s obviously working.