Temperature Sensitivity of Alliant Reloder 26

Has anyone used the Hornady 4DOF Ballistic Calculator? Aparantly they have been testing temp sensitivity on quite a few powders. If you enter your MV and temp, baro when you developed your accurate load, then check the box(Adjust temp velocity) and it brings up a decent range of powders that pretty much all of us use, then add average temp and elevation where you may be going hunting, shooting-it will recalculate your MV for that powder. I can't tell you how accurate it is but I have seen the list of powders grow so I assume the folks at Hornady would be accurately testing. Especially now. Varget and RL16 are the best and Retumbo shows better than H1000 or RL26. I just played around w/ one load and went back and forth w/ all the powders I load with to see their data. Very interesting. Tried to send my chart. We'll see.

Engineering101 said:

you do have to keep in mind that it will drift enough to knock your pet load off its node if the temp changes as little as 20 degrees or so from when you developed the load.

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It very well may, but it also depends on how finicky a rifle is with a load. In my main hunting rifle, I get half MOA or better ranging from 2950 up to 3125 fps, and at 3070 it just comes together and I regularly see groups in the .2's, so that is where I hang out. But even if I was getting 1fps per degree, I would never be in an unacceptable accuracy range

From what most are seeing the .5 fps per degree is close. Some are getting less .25 fps with their set up and some are getting more 1 fps with their set up. It depends on the cartridge and bullet combination. I have so far experienced less than .5 fps per degree in my 6.5 CM.

Bowfishn said:

From what most are seeing the .5 fps per degree is close. Some are getting less .25 fps with their set up and some are getting more 1 fps with their set up. It depends on the cartridge and bullet combination. I have so far experienced less than .5 fps per degree in my 6.5 CM.

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On my test I ran I got very low spread, .15 fps/degree. However, the one thing that wasn't perfect on my test was my rifle temp. While my ammunition was 17°, my rifle was probably about 45°

Cody..thx for the info...
But Maybe that rifle would cool faster if you had it out of the sleeve saying
"For good times..load..point..shoot.....a lot".....

I have a hard time believing that RL 26 is better than H1000.

codyadams said:

On my test I ran I got very low spread, .15 fps/degree. However, the one thing that wasn't perfect on my test was my rifle temp. While my ammunition was 17°, my rifle was probably about 45°

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Cody, to do a proper test, the ammo, rifle, and the shooter must be at 17 F.
Post your results when you get a chance.

Wedgy said:

Cody, to do a proper test, the ammo, rifle, and the shooter must be at 17 F.
Post your results when you get a chance.

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I agree, I got the test as close as I could with what I had available, and I do intend on re-testing. I do think that it certainly shows it in a positive light however, and I also think that it reacts differently in different guns/cartridges. The best way to really see is to test it in your own gun

Tag

Rhovee - I found your comment interesting; RL-26 versus H1000. I would say that neither powder is "better". They are very different powders and both have their uses depending on what you are trying to accomplish. RL-26 will provide significantly higher velocity than H1000 but H1000 is more stable over temperature extremes than RL-26. I like to experiment so I use both but I have to admit that if I had to pick just one of them I'd give up the velocity and go with the stability of H1000. I'm glad I don't have to make that choice.

In "better" i was referring to temp stability. I am going to be using H1000 in a few rifles. I would like to run RL 26 and might, but i will have to check it out for stability for hunting rifles. I always get stuck on the "faster" train.

Every rifle that I have properly developed a load for with RL26 has proved spectacular in temp stability. My 300 WSM changed 7 fps over 53° of temp change. I also have a 300 WM that has maintained a single digit ES with cold bore velocity readings from 28° -72°. I have also worked up a load in my 338 LM that is exceeding my best H1000 and Retumbo loads in both precision with an extra 50-75 fps.

Better than H1000? IMO it's right there with it, if not even a bit more versatile for use in a wider range of cartridges due to it's density and burn rate.

Better than Retumbo? Absolutely! Even though it's a faster burn rate than Retumbo, RL26 generally outperforms in many large capacity magnum cartridges that Retumbo was designed for.

IMO RL26 behaves like a faster burning N570.

Thanks for that info. I am going to give it the go in the 7 SAUM for sure. I might stick to H1000 in the 30/28 Nosler and 338 Edge.

tag