Home Forums Hunting & Shooting Ask The Gunwriters Extreme Temperature Powder Testing By John Barsness

M.D. Just finished reading your well researched article in Handloader on how temperature affects various rifle powders. I can only imagine how many hours you must have spent in the cold to get all that data. It's one of those articles that'll be permanently saved by me for future reference. With my tongue firmly planted in my cheek, I sure would like to have a .270 Winchester load that only dropped 6" at 400 yards.

Glad you liked the article. Just received my copy of the magazine today.

I would also love a 150-grain .270 load that only landed 6 inches down at 400! It should have read 300 yards, but I mis-typed the number, and obviously didn't notice when proof-reading before sending off the final copy. That happens now and then....

Mine should be in the PO box. Can’t wait to read it. It’s the only magazine I take. Thanks for writing the article.

Nice read. Thanks for the work at 0 degrees for the rest of us, MD.

Downloaded the e-mag version at lunch today. Haven't got around to reading it, but thanks for noting the errata JB.

Good article and data points. BTW, I have loaded and tested your .257 Roberts load and it is superbly accurate in my old M77. Nice to know it is good to go in extreme temps also. Happy Trails

My copy just showed up.

Its on the night stand waiting.

Great article, thanks for doing the research! I found it interesting that the 257 Roberts load with Hunter didn't change POI while the 30-06 load did. I'd have assumed that Hunter, or any powder, would behave consistently regardless of the cartridge.

Both the Hunter loads lost just about the same amount of velocity, so the difference was probably in the rifle. As I pointed out, different rifles react differently to variations in velocity. In this instance both rifles were NULA's, with same barrel contour--but the .257's has a smaller hole inside, making it less flexible.

And once again, as stated at the end of the article, one reason for testing a load at different temperatures is that unless we do, we don't KNOW what happens at different temperatures.

Mule Deer, I assume you mean the .257's barrel is less flexible.

Yep, just changed it.

Good point JB, and that was something I was able to do when I lived farther north. Here in South TX not so much. Still, efforts can be made now and then.

I will echo an earlier comment about saving this article. I just read it this afternoon and made a photocopy of the loads page to put in my reloading file cabinet. This is data too good to lose! Thanks again for the effort you put into it.

Hey JB,

I enjoyed reading your article too. Have you ever checked IMR 4198 and IMR 4320 in the 223 Remington or 17 Remington to see how they fare in hot and cold?

Thanks JB, enjoyed that article.

Thanks again for your books, articles and posting here. I've enjoyed your writing for a long time and recently have begun reading some of it to my 8yr old as part of his hunter education. Even the more complex topics are presented in a way he can grasp the main points. I even had him watch the DVD of your advanced reloading techniques. I think by the time he's 12 he'll know more than I knew by the time I was 40.

I've been thinking about temp sensitivity a lot over the last few months as I'm having to move everything to non-lead. I have read many of the comments that you've posted here on the fire and in some of your books but this pulls it nicely together for me.

I'm trying to choose a powder for the .243/80g/TTSX and the .270/110g/TTSX. Seems like it's between:

IMR4451 (Barnes data for H4350 .270 - would need to substitute 4451; Hodgdon data for 4451 .243 for 85g TSX)
or
Hunter (Barnes data)

I hunt mostly in California but sometimes out of state. Temps for hunting would range from 100+ down to mid-20s, rarely lower though I have gotten into single digits in Montana.

Hunter makes this a simpler job and I might get a few more fps, but from what I've read seems I'd be more likely to end up with a temp resistant load if I go the IMR route. I understand that I need to work up the loads and then test them, but what's your educated guess based on my scenario?

htr3,

Glad you like the articles and books!

For your purposes I'd try IMR4451. I've had excellent luck with it in the .243, it should do equally well in the .270 with the 110.

barm,

This is just an educated guess from loading the .222, but IMR4198 would probably be pretty good at various temperatures in the .223. The "traditional" IMR powders tend to be fairly temp-resistant, but it varies with the specific application. I generally use H4198 instead, which is one of Hodgdon's Extremes.

Have never used 4320 in the .17 Remington. When I had one, primarily used Ramshot Big Game, since it flows so much easier through the little neck than extruded powders.

Thanks!

My initial look has not produced published info for 270 Win shooting 110's with IMR4451. Where should I look?

Thanks
Jim