IMR and Hodgdon 4198

[Rimfire McNutjob]

I'm about to buy several 8# kegs of various powders and one of them is 4198. I've been using IMR-4198 in all of my loads and have never loaded H-4198. Clearly though, the Hodgdon version is an attempt to replace or rebrand 4198 away from the DuPont line. However, H-4198 appears to be a newer formulation. I say this because the most recent Hodgdon annual had some cartridges where both IMR-4198 and H-4198 were used and they would suggest that the Hodgdon version slightly outperforms the older IMR powder. They are right butt-up against each other on most burn rate charts.

Should I move to Hodgdon's 4198 and rework my loads? If they are replacing or rebranding DuPont powders, why haven't they done the same for the others ... 3031 for example? Why do 4198 and stop? I don't want to necessarily buy into an obsolete powder (IMR-4198) but I'm not all that excited about redoing existing loads and I'm not really comfortable with just swapping H-4198 grain for grain ... though Hodgdon may have intended that given the use of the same number for the powder.

Advice? Anyone had problems using the H-4198?

[Mike D.]

Not at all. To me, they are equals and seem to perform identically. Some folks may differ, however, but that's the way I take it.

[Hobie]

I think H4198 is a hair slower than IMR 4198 but that may not be true. H-4198 has been around from before the product lines came under one corporate umbrella. There was no real IMR 3031 equivalent. H-4227 has gone away.

It has been a stated goal that some duplicates would be removed from the product lines if lack of sales made it worthwhile. I note that HP-38 and W-231 as well as H-110 and W-296 are still around. Get what you used before.

[Leverluver]

Working up loads in a pressure barrel for the 45-70, it is as Hobie said. H is just a tiny bit slower than IMR but the difference is insignificant. At all out max top end loads (40K) the IMR was only behind in velocity (350 gr) but ~25-30fps. I'd say that difference isn't worth fiddling with.

[1886]

The H version is part of their extreme line meaning that it is largely temperature insensitive. Certainly an advantage. 1886.

[flatnose]

I have not heard of any plans to scrap or replace the IMR powders with the Hodgdon powders. I have loads worked up with IMR, and when my supply runs out, I will just buy more of the same.

[Old Savage]

In reading Hodgdons manual they usually seem to have their loads outperform IMR.

[Modoc ED]

I use H4198 for one of my .444 Marlin loads and another guy in our gun club uses IMR4198. All the particulars of our loads are the same (brass, primer, bullet) except the powder and both perform as if they were mirrors (exactly the same).

Hodgdon's 2009 Reloading Manual on page 64 lists IMR4198 as #58 and lists H4198 as #59 in their Relative Burn Rate Table (Fastest to Slowest).

Even though they appear to be nearly identical (even granulation size and make-up), I would not mix the two.

Finally, I'd say that if someone were already using eigher H4198 or IMR4198 it wouldn't be worth any difference to change.

[Old Time Hunter]

The H version is part of their extreme line meaning that it is largely temperature insensitive. Certainly an advantage. 1886.

I can attest to this. Personally H4198 is my preferred powder for straight walled cartridges as it maintains consistant performance irrelevant as to temperature swings. If my .444 w/240 gr JSP is 2300 fps at 70'F, it will not deviate more than +/- 50 fps at 0'F or 105'F, yet my old IMR loads would change up to 200 fps.

[Rimfire McNutjob]

So it sounds like there's an additive in the formulation for H-4198 that gives it a slight edge in the cold ... otherwise they are as close as two powders can be. Thanks for all of the input on this.

[Rimfire McNutjob]

It appears, from what I've read recently, that the H-4198 is being done in the short cut style now and may thus achieve a higher load density. I wish they would label all of the short cut versions with SC instead of only labeling some while others (H-4198) have also been converted but not labeled as SC.

[Wes]

I could never get the IMR to meter through my Pacific powder measure, but the H4198 runs well through it. The H4198 has significantly shorter kernels to my eye. I've had best luck with the H4198 as far as getting the most out of several calibers such as the 45-70, 444, and the 218 Bee. I'm not sure if it's more accurate in them all, but it's at least as accurate in the rifles I've tried it in.

[El Chivo]

I got bit by a temperature change problem using a different powder, groups went from cloverleaf to off the paper. Now I use a Hodgon extreme powder so that won't happen.

The guy at the reloading store assured me that "everyone uses the IMR version" but I think that's probably out of habit.