Powder issues

[338 dude]

Need ideas from you folks.I am working on reloading for my 300 win mag rifle again.I have an established loads of 69.4 grs of IMR 4350 powder that shoots lights out in cool weather but recently I shot it at about 70 degrees when I got to the range and by the time I set up I guess the temps came up higher than 70 degrees because when I shot the rifle recoil was very sharp!Accuracy was great as it was in the center so I shot again and same thing,I checked my notes and yep the same loads I have been using since 1988 so a third shot was enough to quit.All 3 shots made a single hole.
Question:Is there a temp Insensitive Powder that can shoot a 180 gr bullet 2960 fps so I can keep my custom turret?I was using Hammer bullets that day but if I have them I normally use Accubond bullets.Nosler has 70.0 gr IMR4350 as max so I was under max but that didn't stop the hard recoil and slight ejector marks on the Lapua brass.

185 juggernaut 79.4 H-1000 Lapua brass 215primer cbto 2.890 @2950

 

[vancewalker007]

I'll say H1000 as well. It's too bad IMR7977 isn't available any longer. I was also very temp insensitive and performs a lot like H1000. The other temp resistant powder similar to H1000 is Vihtavuori N565. It may be a little slower in muzzle velocity than H1000 but lots of people are using it these days and getting good results.

 

[Old Rooster]

Like someone else said. It's a hunting rifle and it's shoots great in colder weather as well as warmer with a little pressure. Why fix something that isn't broke. Just don't shoot it in a 100 degree day

Besides hunting I am a casual shooter also as I have 3 300 win mags so I shoot for fun as well as hunting.
I'll always have my old consistent load that has taken too many animals to count but I would still like to shoot in the summer months as well.
Thats why I started this thread,so I could shoot all year long.

 

[Old Rooster]

Thanks guys I am getting great ideas.

 

[Old Rooster]

Just loaded some to test.79.0 gr H1000 should put me pretty close to my old load.
Nosler manual put it at 2980 fps so I may have to come down a couple of grs since the air is a tad thinner up here.
Thanks to all!

 

[chav0_12]

Right before cataract surgery a few weeks ago I stopped at Sheels in Great Falls.I should have asked about H1000 then.
I could always check online.

That's basically what I did, he was driving up from TX, and going along I-25 so I looked and there was some in stock right off the interstate, he said they had a bunch of it too. I'd check online for Scheels, only because they seem to update their local stock. I stop in at Missoula once a month and that's about it. I know when I stopped it at Bob Wards in Missoula I was surprised at some of the powders they had in stock too.

 

[Old Rooster]

185 juggernaut 79.4 H-1000 Lapua brass 215primer cbto 2.890 @2950

Sounds like magic!I still some 185 gr VLD Hunter Bergers,should be similar.
I have a long throat also so I could load long too.

 

[JKB57]

H4831sc is temp stable and worked fantastic in my 300 with 180 accubonds and Nosler 220gr custom competition

 

[Old Rooster]

H4831sc is temp stable and worked fantastic in my 300 with 180 accubonds and Nosler 220gr custom competition

what kind of velocities did you get?180 gr Accubonds?

 

[JKB57]

I don't recall anymore but I don't worry so much about speed as I do accuracy

 

[Old Rooster]

I have to worry about speed as I bought a custom turret for my scope and need velocity to be close to the same I was getting with my old load,around 2960 fps.

 

[Muddyboots]

Need ideas from you folks.I am working on reloading for my 300 win mag rifle again.I have an established loads of 69.4 grs of IMR 4350 powder that shoots lights out in cool weather but recently I shot it at about 70 degrees when I got to the range and by the time I set up I guess the temps came up higher than 70 degrees because when I shot the rifle recoil was very sharp!Accuracy was great as it was in the center so I shot again and same thing,I checked my notes and yep the same loads I have been using since 1988 so a third shot was enough to quit.All 3 shots made a single hole.
Question:Is there a temp Insensitive Powder that can shoot a 180 gr bullet 2960 fps so I can keep my custom turret?I was using Hammer bullets that day but if I have them I normally use Accubond bullets.Nosler has 70.0 gr IMR4350 as max so I was under max but that didn't stop the hard recoil and slight ejector marks on the Lapua brass.

Old Rooster: Thought to consider:
Hammer 180HH is lot longer than an Accubond 180 which can increase pressure depending upon how the bullet seating depth differential between the 2 bullets relative to your rifle throat. You may not have set the Hammer far enough out to accommodate the length difference. Different bullet = different load = different pressure

 

[birddog 68]

Different bullet = different load = different pressure

Not sure how I missed the hammer bullets instead of the accubond but I would say Muddy has solved the problem.

 

[PrecisionRx]

Need ideas from you folks.I am working on reloading for my 300 win mag rifle again.I have an established loads of 69.4 grs of IMR 4350 powder that shoots lights out in cool weather but recently I shot it at about 70 degrees when I got to the range and by the time I set up I guess the temps came up higher than 70 degrees because when I shot the rifle recoil was very sharp!Accuracy was great as it was in the center so I shot again and same thing,I checked my notes and yep the same loads I have been using since 1988 so a third shot was enough to quit.All 3 shots made a single hole.
Question:Is there a temp Insensitive Powder that can shoot a 180 gr bullet 2960 fps so I can keep my custom turret?I was using Hammer bullets that day but if I have them I normally use Accubond bullets.Nosler has 70.0 gr IMR4350 as max so I was under max but that didn't stop the hard recoil and slight ejector marks on the Lapua brass.

Before changing anything, I would chronograph the load at different temperatures. You seem to have a good load developed already. If you see significant velocity differences, then start looking for another powder.