Temp Sensitivity

[Gomer]

I will be in the Eastern Cape in August of 2027. Google says average highs of 72 and lows of 48. Where I live, I typically develop loads in the summer where temps are usually around 80 (at sea level). If that’s the case, I should be good if I settle on a load thats under max pressure here, right?

 

[KEC]

Yes Sir!

 

[matt85]

Most modern powders are pretty stable. You can find charts online for which powders are more sensitive.

 

[Gomer]

Most modern powders are pretty stable. You can find charts online for which powders are more sensitive.

What I am trying to do is eliminate temp sensitivity as a factor. The way I see it I either pick a temp stable powder and hope it’s best for my rifle, or develop a load at similar average temperature and use whatever powder that shoots best regardless of its temperature sensitivity. I’m more concerned with pressure.

The problem is, if I develop a load in July here, I have 3 months of practice time with that particular load if I am hunting at home. If I do the same next year, I will have a month before my trip. Currently, I’m practicing with cheap bullets of the same weight that I don’t intend to take with me.

 

[KEC]

There always seems to be a few powders that stand out in each cartridge for accuracy and performance. I will usually start with one of these powders that is the least temperature sensitive. Example: .308 win- H4895, Imr 4895 or Varget, I would try the H4895 or Varget first depending on velocity and pressure.

 

[matt85]

Unless your dancing on the max pressure line. The most sensitive powder available today will still be stable enough to be safe.

More likely, a temp sensitive powder could cause a POI shift or a reduction in accuracy.

 

[Russ16]

The temp differences you’re referencing aren’t enough to worry about.