Home Forums Hunting & Shooting Ask The Gunwriters Mule Deer & others-Least temperature sensitive slow burning powders?

You're welcome!

So, a Montanan should shoot in temps between -20 and 80 degrees.......





If he plans on hunting opening weekend

Yep!

JB thanks for the reply. I love H4350 but the H4831SC is going to get a try as well! If it shoots as well or better I may switch.

So, Mule Deer, if a guy were to buy a #1S in 300 H&H, would H4831SC get the nod ahead of H4350? Purely hypothetical of course.........

This is indeed a very informative thread, thanks for all the information!

I vote it be sticky-fied. What do you all think?

bigwhoop,

No. I'd probably try both and choose which one shot best.

By the way, I bought a 1-S in .300 H&H and Ramshot Hunter got the nod.

MD,
Ok, thanks very much. Still pondering the purchase.

Some good info, Thanks.

Nifty-250 interesting that 7828 came out slightly ahead of Magnum, I would have bet on Magnum. I am curious how R25 and H1000 would come out in that comparison. I always thought the bigger the charge and the slower the powder the more likely that variations would occur. Probably another myth generated from using lots of old H870.

Inasmuch as it's a problem that I have never encountered, or perhaps ignorance is bliss and I never knew I had a problem it has not been a concern of mine..I have shot a lot of the powders mentioned without incident as far as I know..I wouldn't swear to it but I believe that most gunnuts create problems and many of them strive on them, and hey thats OK too...

Very late to this thread but I thought a historical persepective might be useful. Hodgdon rebadges many of the Astralian made powders, designated AR here in Australia and now owned partly by the French company Thales.

Anyway ... when originally conceived ... the design feature being sought was chamber pressures below 48,000cup in 7.62mm ball rounds at 80degC (conditioned temperature ... ie the ammunition was at this temperature not 80degC ambient) which was a temperature deemed as ordinary daily radiation in outback Australia.

What ADI (Australian Defence Industries) is said to have achieved, is the means to control the 'included microporosity' of the powder kernals. Granules have microscopic cavities that were said to be roughly spherical and from 5-20 microns in diameter, smooth and isolated from each other. Hercules are said to have been the first to discover 'microporosity', but the Mulwala (name of the ADI complex) team led by Alister Wylie are reportedly the first to have discovered a way to manipulate and control it. Not sure about now, but at the time it was a Trade secret ... which probably explains why the Australian Govt sold it to the French. The original claim was 'improved progressivity', that is more velocity for lower peak pressures and little effect of temperature on ballistic properties when compared to IMI-type and Ball powders.

The Malwala team were also said to have determined a relationship between pressure and conditioning temperature and expressed it as a coefficient. Whilst Ball powders display a positive coefficient, particularly at above 50 deg C temperatures, the Mulwala team determined how to manipulate the powder to give positive, neutral and even negative coefficients. The 'AR2206 type' powders (of which the Hodgdon sold powders are derived from ... AR2206 was itself derived from numerous tests of a precursor we knew as AR2201) were all manufactured (and I presume still are) as slightly positive coefficient.

Note that at no time was any claim of 'temperature insensitivity' made and that may be a marketing play. No claim that I can remember was ever made to how it would respond to extremes in conditioned temperatures either. We simply know the AR powders as being minimally affected by temperature variations. And some are known to vary considerably from lot to lot ... but that's another story.
Cheers...
Con

Con,

Thanks for the very informative post.

I prefer to call these powders temperature resistant, rather than temperature insensitive. I have found such powders in general to be much more resistant to cold than heat, but still better than older powders in both directions.

There have also been big advances made in ball powders in temp-resistance in the past decade. I just visited with a company that deals in such powders and got some interesting specifics about how they are made.

Thanks for that very interesting post, Con.

FWIW, I shot some more R17 through my WSM's this evening. Temps/ammo/rifles were around 85-90F degrees. Primers were a little flatter and POI was roughly 2-3" higher at 400-490 yards which is no big deal.
R17 appears to be a very good powder.

A possible article on the subject in the future?

Yeah, I have some powder/pressure articles in the works.

That would be interesting. I'd like to better understand the science behind newer powders. It's not like they are leaps and bounds better, but there does seem to be some meaningful improvements in velocity & consistency in the powders available to the reloader as of late. That's my perception anyway.

MD - I would really like to see the articles. Since dropping Wolff, I'm trying to keep track of you - can you let us know where they will be published? Thanks.

I've got some stuff planned for American Rifleman, Varmint Hunter and Guns--but I am also writing for Wolfe again, so will probably do something for Handloader too.

Just when I`m trying to shorten the magazine list you come out a reason to keep buying a half dozen of them......Glad to see ya back at Wolfe.