temperature sensitive powders?????

[30-06 boy]

i know or have seen some guns shoot great groups at cold temps.the same rifle/load shot at 85 degrees shoots like a shotgun.am i correct in my assumtion that the powder that was used is temp sensitive?i'm going to start load development with 30-06 with imr4350,4831 h4831sc,h1000 re22. are any of these powders temp sensitive?

 

[Jimm]

Must be getting cold where you are too /ubbthreads/images/graemlins/laugh.gif

Seems our post are in the same vein and yes the IMR powders arre more temp. sensitive than the Hogdon powders . Thing is Hogdon bought IMR so I don't know if there is product characteristic sharing in place at this time or not. Hogdon Extreme powders are the leader in this tecnology at this point as far as I know , but .....hey someone might know more on this ( that would'nt take much /ubbthreads/images/graemlins/laugh.gif )

Jim

 

[Centre Punch]

Hi 30-06,
I had this problem when developing loads for my 243 using H4350 before i joined this site.

A hot load on a cold day turned into a super hot high pressure load on a hot day. /ubbthreads/images/graemlins/shocked.gif
I had to beat the bolt handle up with a mallet and on drawing back the bolt the case was stuck to the bolt face. Brass had flowed into the ejecter hole and jammed it in the "in" position.
Some of the primers were pierced, accuracy was crap
Luckily i had some loads made up with Win 760 but my accuracy did not improve /ubbthreads/images/graemlins/frown.gif

I asked my smith about this and after he had stopped laughing he said i had a bit of high pressure and the loss of accuracy was due to massive copper fouling. /ubbthreads/images/graemlins/frown.gif

10 hours of 15 minute periods with Shooters choice copper remover got rid of the fouling and a change to H4350ex cured the cold weather/hot weather pressure problems.

Ian.

"I meant to shoot the pike but the duck got in the way"

 

[300winnie]

So, I have a load worked up for my .300 Win mag using H1000 and 200 grain Accubonds. It clocks just over 3000 fps in 70 degree weather. From what I am reading (and the reason I chose H1000) the temperature outside today (15 degrees F) should not affect the velocity of this load. I have no experimental data, but I am going to test it sometime in the near future.

Next, I have an itch to try something different this winter. I want to work up a load with the 180 Accubond. I have an 8lb caddy of IMR 4831 and an 8lb caddy of H1000. If I am looking for something that is going to remain stable should I even bother with the IMR 4831? /ubbthreads/images/graemlins/confused.gif

 

[wapiti13]

Jimm, Talked to Hodgdon and there are no plans to change IMR powders. Hodgdon might own them, but still made in Canada and nothing is going to cange. /ubbthreads/images/graemlins/frown.gif