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IMR 4350 vs H4350

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07 November 2007, 23:30
GarBy
IMR 4350 vs H4350
Does anyone have an approximate conversion or comparison on these 2 powders as far as charge rates? I'm loading for a 450 NE and can find IMR loads, but not H4350 loads. It appears that in the two different 4831 powders, the IMR requires LESS weight compared to H4831. In both instances, the burn rate charts show the H variety of both powders to be a bit SLOWER than their IMR counterparts.

Thanks.

Gary
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08 November 2007, 00:36
Winchester 69
The Hodgdon and IMR 4350's can be considered interchangeable. As you noted, the 4831's have different burn rates, the IMR being considerably faster.

Check the Hodgdon website for load recommendations. Hodgdon owns IMR, and both are covered on the same site.
08 November 2007, 01:11
GarBy
Thanks, Win....yeah, I did a search for this subject (should have before I posted) and found the same info you state.

Thanks for the response.

Gary
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08 November 2007, 03:05
kraky
I agree that for practical purposes they may be considered interchangable. Actually I've found some of the later lots of H4350 to give as much and slightly more velocity than I4350 which is a "switch" from what things used to be a number of years back. Start a hair low and work up.
08 November 2007, 05:48
Dan H
I would say "nearly interchangeable". H4350 seems a tad slower and denser to me, also yields slightly higher velocities in my 375 H&H.

I would start low and work up as always, and don't substitute later.

Quickload DOES NOT consider them interchangeable....FWIW.

Cheers,

Dan
08 November 2007, 06:56
GarBy
Thanks, gents. Loading for the NE cartridges you can be just a bit off and be OK...just won't regulate. I took the IMR load info and backed off 2-3 gr and will work up with chrono and regulation. I've had such great luck with H4350 in my 404, I just wanted to try it in the 450.

Thanks again.

Gary
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08 November 2007, 10:48
Snowwolfe
For some reason I get better accurracy with H4350 than I do IMR. Just finished working up a 06 load for my son today and then back into my records and sure enough H4350 beat out IRM 4350 for accurracy in every case.


My biggest fear is when I die my wife will sell my guns for what I told her they cost.
08 November 2007, 16:17
GarBy
Snowwolf:

I did A LOT of research on this and other forums and found almost a 50/50 split to the accuracy issue between the 2 powders....with the best accuracy seeming to come the the recent (last 3-4 years) batches of Hodgdon's powder.
I'm interested as much in temp sensitivity as accuracy (NE rifles kick too much to shoot sub moa groups) so my interest was confined to H4350. I'll post my loads and results on the DR forum when done.

Thanks.

Gary
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08 November 2007, 21:07
larrys
I have found AA4350 to be more accurate than the others, although they are all too close to really call. I believe lot-to-lot variation may be more differentiating than manufacturer of any of them.


Larry

"Peace is that brief glorious moment in history, when everybody stands around reloading" -- Thomas Jefferson
08 November 2007, 22:40
Snowwolfe
quote:
Originally posted by GarBy:
Snowwolf:

I did A LOT of research on this and other forums and found almost a 50/50 split to the accuracy issue between the 2 powders....with the best accuracy seeming to come the the recent (last 3-4 years) batches of Hodgdon's powder.
I'm interested as much in temp sensitivity as accuracy (NE rifles kick too much to shoot sub moa groups) so my interest was confined to H4350. I'll post my loads and results on the DR forum when done.

Thanks.

Gary
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That is my experience as well. The IMR 4350 I used was purchased about 18 years ago and the H4350 was purchased last year. Interesting, I never made that connection before.


My biggest fear is when I die my wife will sell my guns for what I told her they cost.
08 November 2007, 22:51
Fjold
All I know is that the H4350 and the IMR4350 are different and it drives me crazy.

My 375 H&H loves IMR4350 with the 260 grain Partition and my 6.5x284 loves H4350 with the 142 grain SMK.

I've tried to get either one to shoot the other powder but it will not work so I'm stuck using both powders.


Frank



"I don't know what there is about buffalo that frightens me so.....He looks like he hates you personally. He looks like you owe him money."
- Robert Ruark, Horn of the Hunter, 1953

NRA Life, SAF Life, CRPA Life, DRSS lite

09 November 2007, 05:20
GarBy
DAMN GUNS ARE LIKE WOMEN.....can't please 'em all the same!

Gary
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09 November 2007, 05:23
fredj338
They are NOT interchangable. IMR4350 is just a bit faster than H4350 in most carts. There really is no conversion factor, you'll have to work up loads using each. In larger bore carts you may not see much diff.


LIFE IS NOT A SPECTATOR'S SPORT!
10 November 2007, 00:35
GarBy
Thanks, Fred.....posted a range report today on the Double Rifle section.....RL15 seems the best....same as in my 470.

Gary
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