300 wsm load development

[BeardWonder62]

In the process of developing a load for my 300wsm. Right now I’m just using H4350 with ELDX 200gr. Seating depth is 2.904 so far it likes 59gr (.520 group) 60 and 61 were 1.03-.750 groups at 100yds. Has anyone use super performance powder or Alliant RL-17 ? This load will be use for mostly ELK and Mule deer. 

[Siwash]

With that bullet my 300 WSM likes 64 grains of H4350…I get similar results to you for groups if I do my part and never felt a need to explore anything else. 

[452b264]

SPP and rl 17 are not  temperature stable powders but H 4350 is. 

[ctafoya]

I'll be re developing my load this year. Thinking about the same bullet your using. What are you getting for speed? 

[BeardWonder62]

I haven’t check the speed yet . Just looking at the groups for now. I’m getting chronograph for Christmas present. But I’ll let you know. 

[L Cazador]

You may want to wait till the Chrono shows up. You wasting your time looking for groups first. Don't worry about that. Most reloaders start backwards. You start with finding a max load first and best extreme spread with the best powder that fits to accomplish these goals. Then you work your way to best group! Start with fireformed brass. Use a moderate load to fireform your brass. Use cheap bullets to fireform.  Keep this in mind, great groups with bad ES usually means you've chosen the wrong powder. Low extreme spreads and bad groups usually mean you've chosen the wrong seating depth. Start at magazine length and work your way back 5 thousandths at a time. Don't use your buddy's pet load, every rifle is different! Use a powder with a temperature coating if you're loading ammo that's going to be shot several month's later. Don't load any more ammo than you'll be using in years time. Just a few do's and don'ts!

[Siwash]

On 12/18/2022 at 10:07 AM, ctafoya said:

I'll be re developing my load this year. Thinking about the same bullet your using. What are you getting for speed? 

I looked up my load data…200gr ELDX is 2930fps with 64grs H4350 out of a 26” barrel 

[MMACFIVE]

On 12/21/2022 at 6:54 PM, L Cazador said:

You may want to wait till the Chrono shows up. You wasting your time looking for groups first. Don't worry about that. Most reloaders start backwards. You start with finding a max load first and best extreme spread with the best powder that fits to accomplish these goals. Then you work your way to best group! Start with fireformed brass. Use a moderate load to fireform your brass. Use cheap bullets to fireform.  Keep this in mind, great groups with bad ES usually means you've chosen the wrong powder. Low extreme spreads and bad groups usually mean you've chosen the wrong seating depth. Start at magazine length and work your way back 5 thousandths at a time. Don't use your buddy's pet load, every rifle is different! Use a powder with a temperature coating if you're loading ammo that's going to be shot several month's later. Don't load any more ammo than you'll be using in years time. Just a few do's and don'ts!

I agree with finding a low SD. 

The  Hornady podcast I posted claims seating depth has almost zero affect on group size with their bullets. They say set them 20-30 thou off and forget it. 

[L Cazador]

19 minutes ago, MMACFIVE said:

I agree with finding a low SD. 

The  Hornady podcast I posted claims seating depth has almost zero affect on group size with their bullets. The say set them 20-30 thou off and forget it. 

Generally, magazine length can be .100-200" off. Strip the bolt and find "bullet touch" first then calculate measurement to lands. 20-30 off is only important from a liability standpoint for Hornady and for you its a safety issue. Sticking a bullet in the lands is very dangerous. Seating depth is however very important as it can influence extreme spreads, velocity, point of impact, and group size!!!By the way that load above is a pretty hot load. Sierra book shows 59 grains of H4350 as max. with an average velocity of 2800! Also the recommended powders are H1000 and Retumbo for the 200 grain bullet. H4350 is faster burning than Retumbo and H1000. Use with caution.

[BeardWonder62]

On 12/16/2022 at 10:33 PM, 452b264 said:

SPP and rl 17 are not  temperature stable powders but H 4350 is. 

Retumbo is not in the Hornady manual for 200eldx . I’m going to try Barnes and Sierra see how the riffle likes them.

[STOMP442]

H4350 is THE powder for the 300WSM. Other powders with similar burn rates will also work well. R17 will probably net you a little more velocity but like others have mentioned not as stable as H4350. R16 would be another good choice. That being said you are getting half inch groups with the load you have found, what more do you want for a hunting rifle? If you do want better groups I would stay away from the ELD-X line of bullets. They are consistently the most inaccurate bullet I have ever tried in multiple calibers. I would go to a Berger or Sierra if you are looking for the best accuracy possible. 

[L Cazador]

1 hour ago, STOMP442 said:

H4350 is THE powder for the 300WSM. Other powders with similar burn rates will also work well. R17 will probably net you a little more velocity but like others have mentioned not as stable as H4350. R16 would be another good choice. That being said you are getting half inch groups with the load you have found, what more do you want for a hunting rifle? If you do want better groups I would stay away from the ELD-X line of bullets. They are consistently the most inaccurate bullet I have ever tried in multiple calibers. I would go to a Berger or Sierra if you are looking for the best accuracy possible. 

Recently checked bullet base to ogive measurement on a box of Hornady ELDX (sample of 10 bullets) had as much as .010" difference while Berger only .002"(sample of ten bullets). While H4350 worked best for me with 168 grain bullets, H1000 and RL26 both temp stable worked best with 200 grain plus bullets.

[MMACFIVE]

3 hours ago, L Cazador said:

Generally, magazine length can be .100-200" off. Strip the bolt and find "bullet touch" first then calculate measurement to lands. 20-30 off is only important from a liability standpoint for Hornady and for you its a safety issue. Sticking a bullet in the lands is very dangerous. Seating depth is however very important as it can influence extreme spreads, velocity, point of impact, and group size!!!By the way that load above is a pretty hot load. Sierra book shows 59 grains of H4350 as max. with an average velocity of 2800! Also the recommended powders are H1000 and Retumbo for the 200 grain bullet. H4350 is faster burning than Retumbo and H1000. Use with caution.

You should listen to the pod cast. It’s very good and will challenge a lot of our previous assumptions. 
 

They are not saying 0.030” off for liability. They saying that seating depth has virtually zero affect and just set it 0.030” off and forget ever adjusting it for their bullets. 
 

You really have to have an open mind about all of your previous knowledge when you listen to it. 

[MMACFIVE]

3 hours ago, L Cazador said:

Generally, magazine length can be .100-200" off. Strip the bolt and find "bullet touch" first then calculate measurement to lands. 20-30 off is only important from a liability standpoint for Hornady and for you its a safety issue. Sticking a bullet in the lands is very dangerous. Seating depth is however very important as it can influence extreme spreads, velocity, point of impact, and group size!!!By the way that load above is a pretty hot load. Sierra book shows 59 grains of H4350 as max. with an average velocity of 2800! Also the recommended powders are H1000 and Retumbo for the 200 grain bullet. H4350 is faster burning than Retumbo and H1000. Use with caution.

This podcast from Hornady about load development is worth listening to. 

 

Some of the take always are neither a ladder test or 3/5 shot OCW groups come close to defining a loads capability. For standard case size 1 grain power increments are adequate vs the .1/.3 gr most of us use. And with their bullets seat them 0.025 - 0.030” off the lands and forget you have a seating depth adjustment abilities. 

 

Of course there a lot more in nearly an 1-1/2 hr podcast but these takeaways spur plenty of controversy. 

 

https://youtu.be/QwumAGRmz2I

[452b264]

Berger will recommend you start .15 off the lands and work back at .5 thousandths. 

If seating depth didnt matter then why can my 300 win go from this to an 1.5 inches?