H4350 vs IMR 4350

[opos]

For a long time I've been watching the scramble for H4350...and the seemingly always out situation while IMR 4350 seems to be available with not much problem...I don't load for the AR's and am just interested in whether this is more a real situation or a marketing or word of mouth matter similar to how some folks view HP 38 and W 231...I've seen lots of "yelling and shouting" and even seen printed load differences between HP38 and W231 while the manufacturer swears they are the same product in a different package..and of course the W231 is often higher in price due to brand name....Over time I've seen "pros and cons" of H4350 for it's lack of temperature sensitivity...but again it flows both ways...is this just sort of one of the never ending conversations?

I shoot a 25-06 and use 4381 and 4381 short cut but there is a reason..the way it meters and how it fills a case with the short cut vs. regular cut...but not sure about "real reasons" for the Unicorn Dust issue in 4350.

Just curious if the 4350s are truly different or is it mostly hype or talk.
Thanks

[pennstater]

They are different. Not a lot of difference, but, it's there. Pretty much like the 4831 powders. Not perfectly inter-changeable. And like you, I like H4831sc in my 25-06. I believe the H4350 is a little faster than IMR.

[hntnnut]

The way I understand it H4350 is not temp sensitive and IMR 4350 is.


Richard

[LynnJr]

Very little difference between the two powder and I use them both.
BUT
Some chamberings have a preference for one over the other so that is what gets used.

[NapalmCheese]

Well, Hodgdon sells both, and supplies data for both so let's take a look at the Hodgdon reloading site.

For a .243 Win shooting 100 grain bullets I see 37-40 grains of H4350, and 38.5-42 grains of IMR4350, the max H load being 51,000 CUP, and the max IMR load being 50,100 CUP.

For a .25-06 shooting 120 grain bullets, I see 44-47.5 grains of H and 48-52 grains of IMR. The max load of H is lower than the starting load of IMR. The max load of H is slightly slower than the starting load of IMR. The max pressure for H is 50,900 CUP, the max pressure for IMR is 50,800 CUP.

In 7mm-08 shooting 140 grain bullets I see 45-48 grains of H, and 43.7-46.5 grains of IMR. Max load of IMR is slightly 1.5 grains higher than the starting load of H. Max load pressure for H is 49,800 CUP, max load pressure for IMR is 50,000 CUP.

Even if they were identical I would expect some small bit of variance just do to lot-to-lot variations, etc.; but this seems to be a pretty big difference to explain away as lot-to-lot variation.

That being said, IMR powders are made in Canada IIRC, and the extreme H powders (4 numbers) are made by ADI in Australia. I wouldn't be surprised if Hodgdon didn't do any load testing, instead just publishing load test results from ADI and whoever makes IMR.

[slamfire1]

When H4350 was first introduced on the market in the 1980's Hodgdon was proud to proclaim that it was charge for charge the same as IMR 4350. Obviously the formulation has changed over the years. In my 6.5 Swede, 270 Win, and 30-06 rifles, it takes one more grain of H4350 to equal the velocities of my IMR 4350 or AA4350. At the time AA4350 was introduced it was proclaimed as a ballistic equal of IMR 4350.

I think what happens is that price competition did not yield the profitability desired so then the manufacturer's start claiming that their blend have unique characteristics, and that sells the product better. As for temperature sensitivity, I have blown primers with "non temperature" sensitive powders and "temperature" sensitive primers. Whatever special capabilities temperature sensitive powders have, I don't have the ability to measure. Maybe someone else has a thermal chamber and pressure gun and can measure pressure versus temperature.

No powder is pixie dust, but some do fit niches very well. I have found both H4350 and IMR/AA 4350 to be outstanding in a number of applications.

[pennstater]

As was said earlier. They're close, just not THAT close. But, then again, handloaders already know this.

[Scottie15]

I've popped primers on lighter charges of IMR 4350 on 100* days and have had no issues with my standard charge of H4350 in 6.5 creedmoor on those same hot days.

[Cypriss32]

I use both. I tend to like IMR4350 is 30-06 better. My personal results are it shoots a little better and gets higher velocities.

[bsumoba]

H4350 in stock

https://www.powder-valley.com

[ar15barrels]

For a long time I've been watching the scramble for H4350...and the seemingly always out situation while IMR 4350 seems to be available with not much problem...I don't load for the AR's and am just interested in whether this is more a real situation or a marketing or word of mouth matter similar to how some folks view HP 38 and W 231...I've seen lots of "yelling and shouting" and even seen printed load differences between HP38 and W231 while the manufacturer swears they are the same product in a different package..and of course the W231 is often higher in price due to brand name....Over time I've seen "pros and cons" of H4350 for it's lack of temperature sensitivity...but again it flows both ways...is this just sort of one of the never ending conversations?

I shoot a 25-06 and use 4381 and 4381 short cut but there is a reason..the way it meters and how it fills a case with the short cut vs. regular cut...but not sure about "real reasons" for the Unicorn Dust issue in 4350.

Just curious if the 4350s are truly different or is it mostly hype or talk.
Thanks

They are different.
The difference is lost on most people.
Most people are buying into the hype that 15fps difference vs 25fps difference per 20 degrees temperature change is actually going to matter.
I have used IMR4350 with great results when H4350 was not available.

[DazedandConfuzed]

I read recently that the shortage is do to the popularity of 6.5CM. According to the article in Shooting Illustrated, Hornady published early reload data using H4350.

[stevec223]

I'm kinda tired of digging for h4350... The new IMR 4451 is actually right between IMR4350 and H4350 on the burn rate chart,,, and is temp stable... Think I will give it a try... I wouldn't doubt the IMR4350 is on the chopping block to disappear soon....
Cheers...