Does anyone know if there is any difference between the two?
IS one hotter than the other?
Thx, Tom

Does anyone know if there is any difference between the two?
IS one hotter than the other?
Thx, Tom

I know IMR4831 is hotter the H4831. Find a powder burn rate chart. It will tell you for certain. I would not interchange the two powders at max pressure levels.

Tom, from the published data I have seen, it would seem that the IMR version is a tad hotter. Not as much as the difference between the IMR and Hodgdon versions of 4831, but there are differences in the published data.

I'd go with the Hodgdon short-cut version for ease of loading, in the absence of any other compelling reason to use the IMR version.

I don't think that I would use the load data for one as if it were for the other one AT ALL. That could be dangerous. :eek:

I have always thought it to be a bad idea on the powder manufacutures part to name the two powders so closely the same. It takes my brain a couple of times to assure itself that I am reading either IMR or H in front of the numbers. If you weren't paying attention you could mistakedly interchange them.

If you are simply asking for burn rates, which I guess you are, I also find that IMR 4831 burns faster than H 4831 but this could be completely different for the 4350.

I tryed H4350 in the .30-06 when the short cut version first came out. It was 100 fps faster than IMR 4350.

Bye
Jack

Huh.... interesting. I guess you never know!

Went back through my Hodgdon #27 manual and found examples in both directions.

It does look like they are pretty close, though.

Hope I didn't muddy the waters too much.

I tryed H4350 in the .30-06 when the short cut version first came out. It was 100 fps faster than IMR 4350.

Bye
Jack
Fellows, thanks for the info.
I wasn't going to mix or exchange the two. Just wondered what the difference was. That explains it.

Seems like a good way to set up a potential accident while reloading when both suppliers use the same powder number like that.
Thx again-
Tom

That was about 1996, so it might not be true of today's H4350. ADI seems to have a lot to lot consistency problem. H322 was the favourite of the benchrest crowd, but it hasn't been since production went to Australia. I had a drop of 90 fps in the .222 with it when I got a new jug.

It just goes to show that you should back off 5%, load up 5 rounds with your old powder and 5 with your new, and run them over the Chrony. While a 100 fps difference with that small a sample isn't statistically significant, it does get my attention.

Bye
Jack

I use both from time to time. The data has shown that the more recent lots of IMR are perhaps a touch slower burning relative to H4350, but as Mike pointed out, there are examples that go in each direction among the current data.

I think they are very, very close in burning rate, but behave a little differently due to their different geometry or composition. I would choose based on whether you want the short kernels, availability, and price, if it were me.

How does that ole saying go?

Close only counts in horseshoes and hand grenades.

Hodgdon makes both of them. Figure sooner or later only one will be on the market. Difference used to be that H was graphite based, and IMR was cellolose based.

How does that ole saying go?

Close only counts in horseshoes and hand grenades.

Of course, if you use "close enough" in handloading, you might inadvertently create a hand grenade!
:eek:

How does that ole saying go?

Close only counts in horseshoes and hand grenades.
Jodum, Did you get your PM?

Tom - I've always found IMR to be just a touch faster that Hodgdon. Unless you're banging up against the max loadings, you should be OK with either. My loads are always below max a bit and the bullets aren't seated right up against the lands. I've never really noticed a lot of difference with the groupings or experienced any pressure problems. This has been in moderate capacity cases such as the 6.5x55 up to the 30-06.

Haven't tried any of the ADI provided H4350 - mine is from at least 10 years ago mfg.

Would suggest you begin at the recommended start loads for both powders and work up to see if you find much difference.

Hodgdon makes both of them. Figure sooner or later only one will be on the market. Difference used to be that H was graphite based, and IMR was cellolose based.

Not too sure about that. I think the graphite is just a deterrent coating. Most single base powders are nitrocellulose based. In any case, Hodgdon doesn't make either powder, they just distribute them. IMR is still made in Canada (where it has been since DuPont stopped making it) and H is made in Australia by ADI.

Just opened a new keg of H4350. It's not black anymore, but brown now like Benchmark only larger grains. I did a double take at first. Thouhgt I opened the wrong can. It doesn't seem to shoot diffferent than the "old" H4350. I haven't run anything across the chronograph to see if there is any speed difference but the accuracy is just as good, maybe better.

RJ

what scares me is not the burn rate but the FACT that even our powder is moving out of the country and both countries are not politacaly friendly to gun owners :confused: :(

Not too sure about that. I think the graphite is just a deterrent coating. Most single base powders are nitrocellulose based. In any case, Hodgdon doesn't make either powder, they just distribute them. IMR is still made in Canada (where it has been since DuPont stopped making it) and H is made in Australia by ADI.

H markets both now don't they? Other than that thanks for the info, I'll not pass on them myths any longer. That's what I like about forums, associates that are friends and educators.

H markets both now don't they? Other than that thanks for the info, I'll not pass on them myths any longer. That's what I like about forums, associates that are friends and educators.


Yep, they market both. And I agree, it is nice to have a friendly group of people here who are knowledgeable and helpful!

This is from my records.

2001
55 grains of H4350 in RP cases with CCI large rifle primers and Sierra 180 grain Pro Hunters gave me 12-26 LESS fps than 55 grains of IMR 4350 in the same cases, same primers and same bullets.

Not a huge difference at all when you are getting 2750 to 2775 fps between the two powders.

Michael - you've backed up my original post. I wasn't sure just what the variation was when I used both powders in the past, but the results were very similar to yours.

Haven't recorded the results of late with the current powders, so really can't say if the small spread is the same, or not.