Improving ES in 300 WM is it just powder selection

Been banging my head on the wall trying to improve the ES and SD on my 300 WM.
All brass prepared and trimmed properly,full length sized, mandrel sized necks, primed with federal LRM primers, all charges weighed on digital and 10-10 scale and were as perfect to the tenth of a grain as I could get them, bullets seated on lee die and all measured to ogive for OAL very consistent lengths. All cases water checked and all were with 1 grn of each between the highest and lowest capacity cases (the deviated shots for high or low extreme spread weren't in the cases with 1 grn off volume). All measured for concentricity and worst was .005 on bullet near tip, the concentricity again didnt seem to be the ones that were low or high on ES.
Tried h4350 with some barnes 180 ttsx and accuracy was horrible however just likely needed OAL adjusted, did the 10 shot method goin .2 at a time after working up safely of course and picked best node and the 5 and 10 shot ES and SD was bad tried a few other charges right in that charge area flat spot. ES was around 60 and SD around 20
Wanting more precision I also tried H414 (didn't wanna burn up the 4350) and some Hornady 168 match, same prep and load workup ES around 70 on a ten shot group after getting the best place on node and SD right around 20. These were accurate at 100 yards even without adjusting OAL

So my question is to really lower those numbers should i look back to my process or more to the powder?
I also think your powders have been too fast burning, I was lucky, tried a short ladder test using IMR 4831, CCI 200's and picked 69.0 grains that gives one hole 100 yd groups with 180 TTSX's and avg 3086 fps with a SEVEN fps extreme spread out of my HSP Gen 1 rifle with 26" barrel.
 
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Been banging my head on the wall trying to improve the ES and SD on my 300 WM.
All brass prepared and trimmed properly,full length sized, mandrel sized necks, primed with federal LRM primers, all charges weighed on digital and 10-10 scale and were as perfect to the tenth of a grain as I could get them, bullets seated on lee die and all measured to ogive for OAL very consistent lengths. All cases water checked and all were with 1 grn of each between the highest and lowest capacity cases (the deviated shots for high or low extreme spread weren't in the cases with 1 grn off volume). All measured for concentricity and worst was .005 on bullet near tip, the concentricity again didnt seem to be the ones that were low or high on ES.
Tried h4350 with some barnes 180 ttsx and accuracy was horrible however just likely needed OAL adjusted, did the 10 shot method goin .2 at a time after working up safely of course and picked best node and the 5 and 10 shot ES and SD was bad tried a few other charges right in that charge area flat spot. ES was around 60 and SD around 20
Wanting more precision I also tried H414 (didn't wanna burn up the 4350) and some Hornady 168 match, same prep and load workup ES around 70 on a ten shot group after getting the best place on node and SD right around 20. These were accurate at 100 yards even without adjusting OAL

So my question is to really lower those numbers should i look back to my process or more to the powder?
put a Lee factory crimp on your rounds and watch your deviation improve
 
Been banging my head on the wall trying to improve the ES and SD on my 300 WM.
All brass prepared and trimmed properly,full length sized, mandrel sized necks, primed with federal LRM primers, all charges weighed on digital and 10-10 scale and were as perfect to the tenth of a grain as I could get them, bullets seated on lee die and all measured to ogive for OAL very consistent lengths. All cases water checked and all were with 1 grn of each between the highest and lowest capacity cases (the deviated shots for high or low extreme spread weren't in the cases with 1 grn off volume). All measured for concentricity and worst was .005 on bullet near tip, the concentricity again didnt seem to be the ones that were low or high on ES.
Tried h4350 with some barnes 180 ttsx and accuracy was horrible however just likely needed OAL adjusted, did the 10 shot method goin .2 at a time after working up safely of course and picked best node and the 5 and 10 shot ES and SD was bad tried a few other charges right in that charge area flat spot. ES was around 60 and SD around 20
Wanting more precision I also tried H414 (didn't wanna burn up the 4350) and some Hornady 168 match, same prep and load workup ES around 70 on a ten shot group after getting the best place on node and SD right around 20. These were accurate at 100 yards even without adjusting OAL

So my question is to really lower those numbers should i look back to my process or more to the powder?
Try H1000, the results will be surprising if you do your part and have a good barrel.
 
Good indication then that the neck tension is not your "primary" issue ...

I agree wholeheartedly with trying LR primers instead of Magnums ... especially if you can get your hands on CCI BR2s or Fed 210 match ...

I also agree that powder can be the issue ... try to stay with those that have a reputation as being very stable/tight ES/SDs in a winmag ... H4831 (not IMR) and H1000 have that rep with the winmag ... If you're shooting heavies (200gr and up) stick with the H1000.

Just my $.02 worth and it is overpriced at that ... 😉
 
Been banging my head on the wall trying to improve the ES and SD on my 300 WM.
All brass prepared and trimmed properly,full length sized, mandrel sized necks, primed with federal LRM primers, all charges weighed on digital and 10-10 scale and were as perfect to the tenth of a grain as I could get them, bullets seated on lee die and all measured to ogive for OAL very consistent lengths. All cases water checked and all were with 1 grn of each between the highest and lowest capacity cases (the deviated shots for high or low extreme spread weren't in the cases with 1 grn off volume). All measured for concentricity and worst was .005 on bullet near tip, the concentricity again didnt seem to be the ones that were low or high on ES.
Tried h4350 with some barnes 180 ttsx and accuracy was horrible however just likely needed OAL adjusted, did the 10 shot method goin .2 at a time after working up safely of course and picked best node and the 5 and 10 shot ES and SD was bad tried a few other charges right in that charge area flat spot. ES was around 60 and SD around 20
Wanting more precision I also tried H414 (didn't wanna burn up the 4350) and some Hornady 168 match, same prep and load workup ES around 70 on a ten shot group after getting the best place on node and SD right around 20. These were accurate at 100 yards even without adjusting OAL

So my question is to really lower those numbers should i look back to my process or more to the powder?
Getting low es can be a witches brew. Seating depth,powder, powder charge all have to come together.Primers? I have seen a week striker spring throw all in a heap. Are you shooting a savage? They are known for their springs giving up. Being you are getting that much variance with a 180 steers me to not getting lit right or you are too close to the lands and the variance in the ogive of the bullet. I built a 300 PRC. Not shooting as I thought it would. Seated a touch deeper and then it shot in the 1,s
 
Thanks for the reply, I actually have a 12 round test on my bench loaded with h1000 waiting for time to shoot them and find a node. I just wanted to make sure that im not chasing a powder when there is something else in my process Im missing. How does 4831 do in 300 I have a couple pounds of that as well.
H4831SC is my go to powder for the 300 WM ...tried H1000, RL 26 and a couple of others...coupled with Fed. 215M primers and 200 gr. Barnes LRX @.090 of the lands ...produces half inch groups regularly as long as I'm doing my job...
 
Is it new brass? If not how many times has it been fired? Do you anneal your cases? Seems to me with that level of case preparation and load consistency, neck tension would be on top of my list. Followed by primers then powder.
 
IMO, your barking up the wrong tree with H4350 in a 300WM. H4350 is an excellent powder, just not for a 300WM. Case fill ratio is too low casing an erratic powder burn. Get your hands on H-1000, or IMR 7977. Either of those are going to be what you are looking for. Once you figure out the powder side of things swap primers with the best load to ware what yields the best SD.
Yep. This.

If shooting 180 grain bullets 4350 can work but it's still on the fast end, you won't have good case fill, which contributes to poor consistency.

even something in the 4831 burn rate might be more appropriate still...h1000 really shines with 200+ grain bullets in the .300 but maybe it's great with 180s too, don't know.

7828ssc
4831
H1000
4955 and 7977 enduron
Rl 22, 23, 25, 26
 
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