[Blkhawk45]

Can someone tell me the difference in these two powders? Can the load data be interchanged? I'm new to loading the 45/70 and have been loading with Unique with really good success. Now ready to move up a little in the fps, maybe around 1300 fps with 405 hard cast slugs and need a slower burning powder.

thanks

 

[DanielE]

Very close in burn rate and yield similar results.

But load data CANNOT be interchanged.

 

[WxGuyKML]

The load data is slightly different, they are different powders though pretty close. I4198 grains are cut a bit longer and burns differently.
In practical use, I4198 gives a bit more velocity in same measure. I do not have a chronograph so can only tell by recoil feel and load data statistics. And point of impact change.
Recommend using hodgon's website for load data. If using Starline brass, remember it has a bit less capacity than Winchester.

 

[Blkhawk45]

I only use Starline cases but was just curious why Hogden sells powder so close to each other. My old Pacific power measure does not meter extruded powder very well so maybe I'll give H4198 a try first.

 

[DanielE]

IMR wasn't always owned by Hodgdon. That's a fairly recent thing. These used to be competing products.

 

[pricedo]

IMR wasn't always owned by Hodgdon. That's a fairly recent thing. These used to be competing products.

I still have IMR cans with Dupont on them.
The starting load with h4198 for the 45-70 load with the Hornady 350 gr fp according to the Hodgdon manual is 48.5 grains.
I found that load kinda stiff (I like the ball joint in my right shoulder right where it is) and load cases with the Lee dipper that throws slightly more than 45 grains.
Good sensible load that does the job.
The Hodgdon data generally is on the ‘hot’ side.

 

[GrayGhost]

Using Hodgdons data IMR uses a little less powder for the same velocity at a little lower pressure : Take Aim at Rifle Reloading Data | Hodgdon Reloading

 

[sandog]

I find IMR 4198 to be an very consistent powder, some of my loads with the 405 grain cast only varied 10 or 12 fps.
27.2 grs. of it was the sweet spot in my 18.5" Cowboy, very accurate and pleasant to shoot, and gave 1150 fps. 30 grains was also nice, and gave 1270 fps.
I also use Starline brass, with W-W primers. Starline brass, as mentioned above, is thicker than Winchester and has quite a bit less case capacity, so beware, if nearing max loads that were tested in the manual with W-W or other thinner brass.
H4198 is just as consistent as IMR 4198, but is easier to flow through a measure. Any IMR stick powder crunches it's way though your powder measure. I still have a pound of IMR, but once it'd gone I'll be switching to the H version. ( And have to work up new loads ).
IMR 4198 is right next to H4198 on the burning chart, it is the faster one. I wouldn't worry at all substituting the slower H4198 for IMR data.
Using the faster IMR when the manual used H, maybe just reduce it slightly.

I don't see why you can't stick with Unique for loads in the 1300 fps. range. I could not find Unique for sale a few years ago ( or any pistol powder ) but did get an 8 lb. jug of Hodgdon Universal. ( Not Clays Universal, that is a much faster burning shotgun powder. I know, kind of confusing on Hodgdon's part, as my jug says "Universal, with Clays Technology". I noticed new jugs of Universal have that removed. Load Clays Universal at Universal charges and it would be a stiff load indeed. Clays is #8 on the powder burn rate chart, Universal is #30. Unique is #26).

It has a very similar burning rate to Unique but a bit slower, but much cleaner burning in my experience.
I found the best accuracy at 12.0 grains,it gave 1100 fps. But 14 grains was also good at 1240 fps. 15 grains should be doable. and might get you close to 1300 fps. Universal is a VERY consistent powder, most of my 5 shot strings only varied 4 or 5 fps.
Only down side to a faster powder like Unique or Universal is the chance of a double charge, inspect rows of cases carefully before seating bullets.
Upside is you'll get the same accuracy, and the same 1300 fps velocity you're looking for, and be using half as much powder to do it.

 

[Blkhawk45]

Many thanks to you guys! I may just stay with Unique. I'm sure I've used Universal in my .45 Colt years ago, something to ponder. I must say that I just love shooting my 1895 so the more shots I can get out of a pound of powder is more money I can spend on bullets!!

 

[Travlin]

Those two powders are right next to each other on the burning rate chart.

 

[67404]

Blkhawk45,

H-4198 is my go to for many hyphenated cartridges. Good accuracy and it drops more consistent charges than the longer grain IMR version.

https://imrpowder.com/

https://www.hodgdon.com/warning/


Also, for a full list of on line load data, see this link i started several years back. There is a 2003 Hodgdon cowboy manual you may also find useful for reduced loads.

http://www.marlinowners.com/forum/reloading/281290-line-free-load-data-references.html

 

[Officer29]

They are close to each other but as was stated the load data is different. I like IMR4198 for my 405gr loads and H335 for my 465gr loads.

 

[onespeedbiker]

Many thanks to you guys! I may just stay with Unique. I'm sure I've used Universal in my .45 Colt years ago, something to ponder. I must say that I just love shooting my 1895 so the more shots I can get out of a pound of powder is more money I can spend on bullets!!

Two other IMR/Hodgdon powders with the same issue are IMR 4895 and H 4895 and come with the same caveat; similar but not the same. If you are still looking for a slower 45-70 I would seriously look at IMR-4895. It is an old powder and you will almost always find a recipe for use with any 45-70 bullet. The Lyman manual shows for their 405g cast, 31g (1312 fps) to 35g (1463 fps). These are lighter "trap door" loads, staying under 18,000 CUP. From there the loads increase for lever action rifles (max 28,000 CUP) and again up for Ruger single shot #1 and #3 (max 40,000 CUP; ouch!). I would advise you to pick up a 45-70 "Loadbook", which will give you a range of recipes for different bullets and powders, by bullet and powder manufacturers. https://www.midwayusa.com/product/694314/loadbooks-usa-45-70-government-reloading-manual

 

[pricedo]

I have found that the Lee 3.7cc dipper of imr-3031 (48.5 grains) behind a 390 - 405 grain hard cast to be a good moderate load.
I can ‘bail’ a powder charge into 50 cases in less than 5 minutes with the dipper.
Accuracy quite good and acceptable but not spectacular at 50 & 100 yds.
After all I’m shooting an off the rack meat fetcher (Remlin 1895GS) with a 18.5” bbl not a $10K bench rest rifle sporting a krieger bbl & surgeon action.