How temperature sensitive is H380 in your experiences?

thanks

My 22-250 loads are 38/H380 55grs. NBT fed 210M primers r-p cases avg high 35's in summer and at 12 degrees avg high 32's. First group shot 3/8 inch. next 2 groups went 1.5 and 2 inchs. So in case I would say very temp sensitive.

Rich

Could temperature sensitivity with ball powders be a function of difficult ignition? If so, would magnum primers make a difference? Does anyone have any experience with this?

Hodgdon makes a line of "EXTREME" powders which are intended to be less temp sensitive. H-380 does not fall into that group of powders. Exactly why I do not use H-380. Minimize the variables.

Still though, I’m curious as to how temperature insensitivity is achieved in a chemical reaction that takes place at 2000 (or whatever it is) degrees Fahrenheit. It would seem that at that temperature the ambient temperature wouldn’t matter too much. So does that suggest that it’s function of ignition?

Or does an environmental difference of, say, 50 degrees actually affect the reaction significantly? I’m just asking.

Also, if it’s the latter, does anyone have any idea how Hodgdon (ADI, actually) achieves this temperature stability? Obviously it would be proprietary information, but I’m still curious.

And yes, I know I can just load powder X in cartridge Y but the whys and wherefores of it are of interest to me simply because they are of interest to me.

I would get on the Hodgton website and shoot them over a email. Most oftion companies of that size are more the happy to reply. Accuret powder set me a bunch of reduced load data for cast bullets with in 12-24 hours

From about 55deg <-> 118deg, it has been my choice for "Who buys the BBQ!" Loads with 168gr Sierra MatchKings in various 308Win rifles for a very long time. I feel sure I've not tried those Loads in colder temps.

With all the new Powders available though, there might be something better just waiting to be tried.

Best of luck to you.

quote:

Originally posted by James Kain:
I would get on the Hodgton (sic)website and shoot them over a email. Most oftion (sic)companies of that size are more the (sic) happy to reply. Accuret (sic)powder set me a bunch of reduced load data for cast bullets with in 12-24 hours

Don't hold your breathe emailing Hodgdon. I've never gotten a reply. Ever!

Accurate Arms (Western Powders)ballistics expert replied the very same day.

I ask Hodgdon for the specific gravity of Varget so I could calculate a loading density. One of the Hodgdon boys refused to give me an answer.
I never bought any Varget and to this day avoid buying their powder if I can.

quote:

Originally posted by SR4759:
I ask Hodgdon for the specific gravity of Varget so I could calculate a loading density. One of the Hodgdon boys refused to give me an answer.
I never bought any Varget and to this day avoid buying their powder if I can.

I hear what your saying. I have used IMR and Hodgton sense I started reloading about 3 or 4 years back. I m just now starting to expand to other company's. Most I ever ask powder company's are to help with load development and there recommendations for starting and max loads. Also subsonic and cast loads. I have yet to try to contact Hodgton about such things. I will try but sounds like I shouldn't hold my breath.

quote:

Originally posted by onefunzr2:

quote:

Originally posted by James Kain:
I would get on the Hodgton (sic)website and shoot them over a email. Most oftion (sic)companies of that size are more the (sic) happy to reply. Accuret (sic)powder set me a bunch of reduced load data for cast bullets with in 12-24 hours

Don't hold your breathe emailing Hodgdon. I've never gotten a reply. Ever!

Accurate Arms (Western Powders)ballistics expert replied the very same day.

oh and thanks for the tip

quote:

Originally posted by SR4759:
I ask Hodgdon for the specific gravity of Varget so I could calculate a loading density. One of the Hodgdon boys refused to give me an answer.
I never bought any Varget and to this day avoid buying their powder if I can.

SR - you should be able to find your answer here:

http://www.baitshopboyz.com/fo...s.asp?TID=13778&PN=1

I don't know how temp sensitive H380 is but I used it for years and years (and still do) loading it into 1000's of cases in hot Oklahoma and shooting it into cool Wyoming Pdogs. Never the reverse however.
Our ammo was always kept in some sort of carrier and never left laying out in the sun but we never kept it in a cooler or any of the extremes I heard tell.
We never had any gross over pressure signs and any change in POI, we wrote up to change in altitude. And they were minor. 'course we were shooting well-bedded Remingtons.