Powder issues

[SSG Graybush]

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.

180s, I'd use H4831sc or H1000. I'd start with H4831sc. I've found for 150's, RL16. 165-180, H4831sc. 200-208's H1000. RL16, Hodgdon "H" powders and Varget are pretty temp stable. You can find charts for fps variances per degree of temp on line. You need this info for your ballistic app to adjust correctly.
And always remember, if you develop a load in the winter it could be over pressure in the heat of summer.
I wouldn't get hung up on trying to match that speed, a dial is cheaper then components. You should chase constancy, sub .5 moa and a ES <15 fps.

 

[asd9055]

I have not used IMR7828 much even though I have 2 pounds.I have had times where I know for sure IMR4350 powder is very much temp sensitive and was told all IMR powders are made the same way and all are temp sensitive.
While I hunt in cool weather I shoot all year and have had times where I knew I needed to stop shooting as I was ruining brass by keeping on.
That was my younger days.Now I try to shoot in mornings and evenings in summer and skip the mid day shooting altogether.
Glad your having success with IMR7828.What velocities and what bullet weight?

I use IMR7828sc in my 300WBY with 180s, and over 3,000 fps. you might be able to get your desired velocity in your 300WM

 

[Old Rooster]

180s, I'd use H4831sc or H1000. I'd start with H4831sc. I've found for 150's, RL16. 165-180, H4831sc. 200-208's H1000. RL16, Hodgdon "H" powders and Varget are pretty temp stable. You can find charts for fps variances per degree of temp on line. You need this info for your ballistic app to adjust correctly.
And always remember, if you develop a load in the winter it could be over pressure in the heat of summer.
I wouldn't get hung up on trying to match that speed, a dial is cheaper then components. You should chase constancy, sub .5 moa and a ES <15 fps.

You make a valid point my friend.I am not sure what I paid for that turret and don't remember where I put the receipt.
A small part of feeding our habit,I mean hobby, so I may just find a load I like and my rifle like's and see if this present turret is close or buy a new one.Thanks for the insight

asd9055 I too shoot a 300 weatherby so I may try IMR7828 in it and see what I get.
Do you shoot it in the summer also?

 

[WYO300RUM]

You make a valid point my friend.I am not sure what I paid for that turret and don't remember where I put the receipt.
A small part of feeding our habit,I mean hobby, so I may just find a load I like and my rifle like's and see if this present turret is close or buy a new one.Thanks for the insight

asd9055 I too shoot a 300 weatherby so I may try IMR7828 in it and see what I get.
Do you shoot it in the summer also?

A couple years ago the CDS Turret's were $100.00. you got one free with a new CDS scope. I just had an email from Luepold about a deal going on with CDS dials. I'll see if I can find in trash.

 

[asd9055]

You make a valid point my friend.I am not sure what I paid for that turret and don't remember where I put the receipt.
A small part of feeding our habit,I mean hobby, so I may just find a load I like and my rifle like's and see if this present turret is close or buy a new one.Thanks for the insight

asd9055 I too shoot a 300 weatherby so I may try IMR7828 in it and see what I get.
Do you shoot it in the summer also?

My summers are HOT, the test load for IMR7828 in 300WBY was with 180 grn TSX, CCI 200 (NOT magnum) primer and IMR7828sc at 92 degrees, only 3091 FPS. COuld go higher but that was extremely tight group
I had an OLD german WBY, 12 twist, that liked 180 BT, IMR4350 and Remington 9 1/2 (NOT mag primer), but that load is deemed high now, and I have since retired that rifle (Its older than I am by a year) and replaced it with new MKV

 

[Old Rooster]

So IMR7828 is in fact not as temp sensitive as IMR4350 right?

 

[WYO300RUM]

You make a valid point my friend.I am not sure what I paid for that turret and don't remember where I put the receipt.
A small part of feeding our habit,I mean hobby, so I may just find a load I like and my rifle like's and see if this present turret is close or buy a new one.Thanks for the insight

asd9055 I too shoot a 300 weatherby so I may try IMR7828 in it and see what I get.
Do you shoot it in the summer also?

A sale for $52.00

https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://www.leupold.com/custom-dial-system&ved=2ahUKEwiyj87kqoyAAxUSHDQIHf-LCW4QFnoECAwQAQ&usg=AOvVaw2VBjtRQ69qaKWfj6jWz0gH

 

[asd9055]

So IMR7828 is in fact not as temp sensitive as IMR4350 right?

I would not swear to it. Perhaps those who test in extremes or read more than I will chime in. I just use different WBY/Bullet/Powder other seasons.

EDIT, according to what I saw online, IMR7828 is NOT temp stable. In fact the perhaps only the IMR Enduron line were considered stable, but I believe they had other issues and have been removed from the market. What I heard.

 

[Old Rooster]

A sale for $52.00

https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://www.leupold.com/custom-dial-system&ved=2ahUKEwiyj87kqoyAAxUSHDQIHf-LCW4QFnoECAwQAQ&usg=AOvVaw2VBjtRQ69qaKWfj6jWz0gH

Thanks buddy,I am sure I paid at least twice that much.
I copied and pasted to my desktop

 

[WYO300RUM]

Thanks buddy,I am sure I paid at least twice that much.
I copied and pasted to my desktop

 

[Pa Grizz]

I have been using 72 grains of IMR4350 with 180 gr Sierra BT in any kind of weather IF I do my part I have never had any problem With my 98 Mauser with a Douglas Supreme barrel