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powders

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25 July 2002, 12:28
BEN243
powders
In what order (least to most) would rate the following rifle powders (IMR, Hodgdon, Alliant, and Vihavuori) as far as them being temperature sensitive ? Ben
25 July 2002, 12:34
<Varmint Hunter>
Hodgdon "EXTREME" series powders are reportedly extremely temperature insensative. They have relatively little change in velocity at temeratures from 0-125 deg.
I am not aware of this claim being made by any of the other manufacturers that you mentioned.
25 July 2002, 13:09
ricciardelli
I'm not a believer in the recent rage about "temperature sensitivity". I have my reasons...

I work-up a load when the weather is nice, generally between 70 and 80 degrees. I use those loads in temperatures anywhere from 50 below to 125 above, and have never noticed any major difference in performance or accuracy.

In addition, remember, that most of the IMR powders (and their off-shoots) were surplus military ... and other than the M-16, I don't recall ANY military ammo failing to fire because it was too cold or too hot...
25 July 2002, 14:10
Pecos41
I think the greatest issue to the reloader/shooter about powder and temperature sensitivity is going to occur from a HOT barrel.
Rarely does a hunter run into this issue. Usually on a hunt there are a few rapid shots and it's over one way or the other.

But I've had some definite temperature reactions from powders while plinking and "rock hunting" and such things where there is consistent (although not necessarily rapid) firing. Gun barrels can heat up like branding irons pretty fast and if a round is chambered in this situation and allowed to sit inside a barrel that may be 300-400 degrees hot........well, it's going to elevate your pressures considerably. Machine guns get into actual "cook off" situations, although I've never heard of a rifle, even semi-auto, getting this hot...and I've probably got mine as hot as anyone a few times.

Anyway, this is not much of an issue of concern for most folks...unless you are loading up to the razors edge and the last thing you need is increased pressure. But for all normal applications I wouldn't worry about it.

For what it's worth, the powder I've had the wildest temperature reaction from was IMR4895.