300PRC Reloading Advice

[LocalJW]

I will be starting to load for my 300prc tomorrow. This is my initial plan.

Brass: Lapua
Bullets: 205bergers
Primers: Winch LM
Powders: RL26, N555, N565, N568, N570, H1000

1) My plan is to take the upper half of each powder range Berger provided.
2) Load 1 bullet for every grain until I am 2 grains over max charge for each different poweder
3) Seat the bullets 20 thou off
4) Shoot each bullet from each powder (roughly 7-12 bullets per powder) each into their own target @ 100 yards
5) Look for similar POI of each target (hopefully 2 or 3 of the powders have some POI that are similar within a 1-3gr range)
6) Then take the middle of that potential node to investigate, then load 20-30 of that exact load, and shoot into a single group.
7) Narrow the 3 or so powders down to the best performing group




Any opinions

 

[Dmagna]

I have had zero luck with N570. I have tried it in two 300 PRCs, both had excellent accuracy but the SD and ES were crap. Would always have a spike of 50+ fps on one or more shots. H1000 gave me the same accuracy but smooth SD and ES. Just about 50fps slower at 2950 with a Berger 215 out of a 26" barrel.

 

[nwmnbowhunter]

I think you have a good plan but that's going to take a long time. And you will have hard time keeping barrel cool.

If you plan on shooting rifle quite a bit i would avoid n570. I can only shoot 2 rounds at a time and have to let barrel cool off. It has been awesome for me though. Fast and accurate.

H1000 will give you more freedom and longer barrel life. Very consistent.

RL26 has been really good for me as well. Pretty fast and accurate.

One rifle is using n570, other is h1000 right now.

 

[jraulsten]

I will be starting to load for my 300prc tomorrow. This is my initial plan.

Brass: Lapua
Bullets: 205bergers
Primers: Winch LM
Powders: RL26, N555, N565, N568, N570, H1000

1) My plan is to take the upper half of each powder range Berger provided.
2) Load 1 bullet for every grain until I am 2 grains over max charge for each different poweder
3) Seat the bullets 20 thou off
4) Shoot each bullet from each powder (roughly 7-12 bullets per powder) each into their own target @ 100 yards
5) Look for similar POI of each target (hopefully 2 or 3 of the powders have some POI that are similar within a 1-3gr range)
6) Then take the middle of that potential node to investigate, then load 20-30 of that exact load, and shoot into a single group.
7) Narrow the 3 or so powders down to the best performing group




Any opinions

Be very careful using load data from Berger. I don't know if the issue has been corrected or not, but Berger was previously giving out 300 PRC data that was very dangerous and well above acceptable pressures, particularly with N570.

 

[LocalJW]

I think you have a good plan but that's going to take a long time. And you will have hard time keeping barrel cool.

If you plan on shooting rifle quite a bit i would avoid n570. I can only shoot 2 rounds at a time and have to let barrel cool off. It has been awesome for me though. Fast and accurate.

H1000 will give you more freedom and longer barrel life. Very consistent.

RL26 has been really good for me as well. Pretty fast and accurate.

One rifle is using n570, other is h1000 right now.

My intent, was to go out in 2 trip and do all of the single shot ladders. 3/5gr increments for the powders.

Then go back out to try and seat depth another day

Then from there do 1 more trip with 20+ bullets to confirm

 

[LocalJW]

Be very careful using load data from Berger. I don't know if the issue has been corrected or not, but Berger was previously giving out 300 PRC data that was very dangerous and well above acceptable pressures, particularly with N570.

Here is the data I received

 

[2buffalo]

Doing what you are will probably get you there but in my opinion wasting time and components. At 100 yds I would do an OCW test with one powder in .5 grain increments until you hit pressure. This will allow you to do two steps in one. Then go seating depth and the final step would be neck interference. I have also just did a 300 PRC with seating depth with a middle range load first that worked fairly well. I started with N568 which worked well then Retumbo because I had more Retumbo than N568. They both produced about the same results.

 

[quigley257]

RL26 has been fantastic in my 300 PRC.

 

[jraulsten]

Here is the data I received

That max load of 88.9 grains of N570 is insane.........My load with 215s was 80.6 grains and that was not a light load by any means. That was pushing the 215s just over 2900 FPS.

 

[LocalJW]

That max load of 88.9 grains of N570 is insane.........My load with 215s was 80.6 grains and that was not a light load by any means. That was pushing the 215s just over 2900 FPS.

Good to know.

So maybe I should start with the minimum and not half way.

 

[LocalJW]

Doing what you are will probably get you there but in my opinion wasting time and components. At 100 yds I would do an OCW test with one powder in .5 grain increments until you hit pressure. This will allow you to do two steps in one. Then go seating depth and the final step would be neck interference. I have also just did a 300 PRC with seating depth with a middle range load first that worked fairly well. I started with N568 which worked well then Retumbo because I had more Retumbo than N568. They both produced about the same results.

OCW as in like a 3 shot or 5 shot group in .5 increments? So maybe shoot over a total of 30 or 40 bullets across a 4-5 grain change?

I've heard that .5 is not much over 65 grains and to do .75 grain or 1 grain changes but I could be wrong

 

[LocalJW]

Doing what you are will probably get you there but in my opinion wasting time and components. At 100 yds I would do an OCW test with one powder in .5 grain increments until you hit pressure. This will allow you to do two steps in one. Then go seating depth and the final step would be neck interference. I have also just did a 300 PRC with seating depth with a middle range load first that worked fairly well. I started with N568 which worked well then Retumbo because I had more Retumbo than N568. They both produced about the same results.

I thought by shooting .75 grain increments over 5-6 grains, 1 shot each, would yield me a potential node over a 1-3 grain change when looking at POI of each single hit.

So shoot 10-12 bullets total instead of 30-40. I thought it would save components. I've seen the ladder test done like that before I believe

 

[2buffalo]

I thought by shooting .75 grain increments over 5-6 grains, 1 shot each, would yield me a potential node over a 1-3 grain change when looking at POI of each single hit.

So shoot 10-12 bullets total instead of 30-40. I thought it would save components. I've seen the ladder test done like that before I believe

It will. But at 100 yds it may or may not show a true node. I can send you a picture of a good OCW test when I get home tonight and explain.

 

[LocalJW]

It will. But at 100 yds it may or may not show a true node. I can send you a picture of a good OCW test when I get home tonight and explain.

I thought by shooting .75 grain increments over 5-6 grains, 1 shot each, would yield me a potential node over a 1-3 grain change when looking at POI of each single hit.

So shoot 10-12 bullets total instead of 30-40. I thought it would save components. I've seen the ladder test done like that before I believe

So maybe shoot it further at 200 or 300?