W760 temperature sensitivity question

caporal

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Hi

I'm trying to find info about W760 sensitivity in COLD weather for moose season in northern Quebec

It's for 9.3x62 with 286 partition.

Thanks
 
The number to the right of the powder is the feet per second change for each degree of temperature change. Meaning the higher the number the more temp sensitive the powder.

33XPgx3.jpg
 
The number to the right of the powder is the feet per second change for each degree of temperature change. Meaning the higher the number the more temp sensitive the powder.

33XPgx3.jpg

How did you get such a specific chart for 9.3? Or is this just numbers with no cartridge, primer, bullet or any other info that would matter?
 
All I use in my Rem 700 classic .250-3000 deer didn't seem to fall any different at 300 yards in -35c than @ 0 C
 
Everything works better with magnum primers, especially when the temps start dropping.

Pretty much all I use even in the 7.62x39 CZ527 groups shrank 50% switching to mag primers easily under 1/2" @100 yards.Deer under 200 yards get a truck ride.
 
I used it in a 243 Win. To be exact it was H414, which is the same as W760 from all accounts.

It isn't the best powder for temperature stability. I've since switched to a different powder that's not as sensitive.

Point of impact isn't the only concern. A max load that's developed in cool weather may be over-pressure in hot weather.

My rifles get used year round, I don't need temperature sensitivity in my ammo.
 
Don`t know about cold weather performance, but years ago 760 "locked-up" a bolt (Savage 110 .22-250) while crow hunting in July.The load was developed in April. Never used it agin for anything. Switched to H4895 and never looked back. Don`t like ball powders in general, find them very dirty and too temp. sensistive.

The worst powders for temp sensitivity that I have experienced are 760, H380 and H335.
 
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Loading ammo for hunting is a bit different than making ammo for plinking.

First, before going on the hunt, cycle all the ammo through the magazine and chamber. make sure it all fits.

Second, it has to work at warm and cold temps. I have been on hunts where it was very cold. We had to wash the lube out of the bolts with gas to make sure the rifle would fire. And I have been on hunts where it was a lot warmer than expected.

If you have to use W760, develop the load now. It would work in warm weather and be a bit slow in cold. Not a big deal unless you are shooting beyond 200 yards.

If it was me, I would load H4350 and get better cold wx performance.

If I had to use 760, I would load it hot, with a magnum primer and be happy with it.
 
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I used it in a 243 Win. To be exact it was H414, which is the same as W760 from all accounts.

It isn't the best powder for temperature stability. I've since switched to a different powder that's not as sensitive.

Point of impact isn't the only concern. A max load that's developed in cool weather may be over-pressure in hot weather.

My rifles get used year round, I don't need temperature sensitivity in my ammo.


IMHO, that's a hold over from much older powders than relatively recent Ball type powders. It's only when you're loading close to maximum pressures, for your rifle, that you will have to be concerned about over pressure at high temps.

Big Ed P51, recently posted a chart on how much temperature effected some different powders, concerning pressure and velocity with medium to slow burn rates.

The rise isn't nearly as much as some pundits would lead you to believe, unless the load is already pushing safety limits.

Still, I like that you're thinking in a safe manner.
 
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