Be aware that these powders are not the same burn rate. They do not use the same data. It will be close but not exact. Many get better accuracy out of H4350. If you shoot in a wide range of temps then yes temp sensitivity is an issue. It is mainly affected with high temps. The longer the range you shoot the more temps will effect your point of impact. Higher temps raise pressure. One load that is OK at 70* may have too high pressure at 90*.
Some rifles prefer one 4350 over the other. My 243 Sako doesn't like IMR but likes the Hodgon. My Winchester likes only the IMR 4350. You gotta give'm what they like (the not what you want. That's what reloading about finding what the rifle likes.
Temp sensitivity is a big issue, not necessarily for accuracy, but for consistent point of impact, especially for long range shooting (as previously stated). I shoot Hodgdon powders almost exclusively in my rifle due to the fact that they are "extreme" powders. I have the ability to shoot my rifle from 0 - 90 degrees and not worry about a major shift in impact.
These powders are completely different powders with different burn rates. Just because one shoots, doesn't mean the other one will. Try it.
This topic has been tossed around alot here lately and it seems that the same people keep bashing hodgdon extreme powders when they have not tested them. Testing does not mean what you are seeing out of one rifle. Are Hodgdon powders the only powders that are less temp sensitive? No, but from the testing I have done they do live up to their billing. I have also found the VV N500 series to be stable in what little testing I have done with these. Powders can be like bullets in some guns, some are less temp sensitive in some barrels and some are not. They have to be shot and tested to see. I love RL22 in my 7MM STW but the velocity is all over the place when temps go up or down so I don't use it. I was discussing this subject with a field staff member of Barnes Bullets two nights ago and he said that they had done a test on this subject including primers. I asked if it was accessible on the internet and he said yes it was actually sent out in their July newsletter. There is only a few Extreme powders listed but as you will see they are very stable powders. Ramshot Magnum intrigued me in this test being that it is a ball powder. I wil be trying it in the future. So here is the link below. In the future it would be helpful to the newer handloader that we keep our opinions seperated from the facts. Just because one powder showed less sensitivity in one barrel/gun compared to an Extreme powder does not make it the rule of thumb. These things need to be stated so as not to confuse the new handloader. I have been handloading for over 30 years now and I am learning something new all the time. Do I know everything, NO WAY!! but if I don't believe something or think it is hype I will test it first to discount it before giving my two cents. Just as a side note, in looking back in my records I noticed that I got more velocity with the Extreme powders before they were labeled as Extreme. This could be just a change in manufacturing lots or it could have something to do with coating that is put on these powders. HMMM!!
Thanks for posting that info. I will never again question the temperature stability of a powder. The IMR 4350 showed a 130fps change with a temperature range of 160 degrees. That is ridiculous. There was only 80fps change from ambient to -40 degrees.
Unless I were shooting at game past 800 yards I couldn't see how this would even be an issue for game size targets. If you're shooting long range for accuracy then it still doesn't matter because when you get there you'll adjust your sites.