300 win mag, Powder,Bullets, High ES

[magedon44]

Hey guys, Ive been testing my 300 win mag, with 190 berger VLDs and bwtween 73-75 grs in H4831sc, with all the testing ive done in .5 gr increments, Im still getting 50fps extreme spreads, but still shooting .5 -.75 moa, Im thinking about changing powders. What would be my best bet to try?

 

[Methow Packer]

Try IMR 7828SSC. Slower than H4831. Not too temp sensitive . I'm at 76.0 grains with 185Berger VLD seated .010 chrono 3100 FPS with ES 22 from a Brux 26" stainless with no pressure signs. .05 MOA. Consistent from one session to another

 

[BountyHunter]

Go to standard primer if you are using magnum and stay with 4831 for now. Try F210 primers

 

[FEENIX]

Hey guys, Ive been testing my 300 win mag, with 190 berger VLDs and bwtween 73-75 grs in H4831sc, with all the testing ive done in .5 gr increments, Im still getting 50fps extreme spreads, but still shooting .5 -.75 moa, Im thinking about changing powders. What would be my best bet to try?

I'm getting 3043 FPS 32 ES 14 SD .5 MOA with the 190 VLDs out of my factory SAKO M995 23 1/2" 1:11 using 75 H4831SC CCI250 .020" off the lands.

 

[benchracer]

Hey guys, Ive been testing my 300 win mag, with 190 berger VLDs and bwtween 73-75 grs in H4831sc, with all the testing ive done in .5 gr increments, Im still getting 50fps extreme spreads, but still shooting .5 -.75 moa, Im thinking about changing powders. What would be my best bet to try?

I would try some different primers if you can get your hands on some. Also, I don't know what brass you are using, but you may wish to sort it by weight or fired case capacity to ensure that you have consistent case volume. If you haven't already, tuning for seating depth might help as well.

If you are getting .5 to .75 MOA after only tuning the powder charge, I would say that you are on the right track. You just need to fine tune a little.

 

[stonehands1]

Well since you have good groups I would say it likes the bullet, seating depth. I would first try Br2s or any large rifle primer and it will probably settle down.
Also anneal all your brass and neck turn if convenient for consistent neck tension. These can all be done without burning precious powder developing a new load. If no luck then I would try diff powders.

7828sc is my go to for 7mm and works well in 300wm.
Rl26 has great speed
H1000
Retumbo
7977

 

[FEENIX]

After nearly 8 years, I hope that the OP has figured out his load development.

 

[magedon44]

Lmfao , that rifle is looooooooong gone

 

[stonehands1]

how did I miss that!