Which 4198 are they recommending?

[pertnear]

I just started reloading the .256 Win Mag (rifle) & there doesn't seem to be much "new" loading data around. No problem though, I just went back to my library of trusty old reloading manuals for help. They all seem to recommend 4198. What is that - H4198 or IMR4198? With a little research I did discover they both have different burning rates, along with a stern warning. If I'm starting with minimum loads in this small capacity cartridge, am I making a mountain out of a mole hill? I have both powders but A LOT more IMR than H.

TIA...

BTW: If you have a good .256 WM load or two to share, that'd be good too!

 

[Adam in WI]

Call the Sierra hotline, they may be able to offer some insight.

 

[BenPerfected]

Another idea is to call Powder Valley and see what they think

 

[243winxb]

In 2003 the Hodgdon Powder Company purchased IMR powders.

Hodgdon makes no powder.

IMR 4198 has been made in Canada & Australia, since Hodgdon started screwing with it.

By volume,IMR4198, there can be as much as 1.1 gr difference in weight. 18.5 gr vs 19.6 gr. with the measure at the same setting. This was older Canada vs Australia. .

https://www.thehighroad.org/index.php?threads/4198.805538/

 

[jackieschmidt]

I have been fooling with 4198 for quite a few years in my 30BR.

Up until about 8 years ago, most of the H 4198 was black. After that, i think right around the time they started putting that Extreme logo on the jug, it all had the greenish is color it has now. Both shot equally well.

IMR never seemed shot as well in my 30BR. Years ago, I borrowed some from a fellow shooter. But then he had no idea how old it was.

 

[243winxb]

ADI has added something to there powder that come here, to make it darker.

 

[243winxb]

http://www.ilrc.ucf.edu/powders/sample_detail.php?powder_id=1

Photos of the same powder. Some very different in appearance.

 

[biggun2869]

IMR was what used to be used. I don't know what year Hodgdon started selling 4198. I would go with a starting load of IMR and go from there. IMR seems to have fallen out of favor in the last 10 years or so but I really don't know why. They are all owned by the same people now so what difference does it make?
That guy is right when he says hodgdon never made powder, the history is right in their manuals. The old man (Bruce) resold military powders to start with then started importing it to cover the numbers as needed. Good reading, especially if you like a little history about our sport. Gary

 

[Gb300wm]

Unless specified, IMR 4198 is usually the go to powder...

 

[pertnear]

Thanks everyone for all the helpful posts!

 

[jsn]

Hodgdon's #27 Data Manual only has data for H4198 for both rifle and pistol, this was the last book they published that had other powder company products. Hornady &th Edition only shows H4198 for 87gr jacketed bullets. Lee's 2nd Edition, 2011 reprint, only shows H4198, the same data as Hodgdon #27.

 

[243winxb]

 

[Ropemaker]

The 256 is a fun little round, used it 40 yrs ago in T/C 10" bbl for IHMSA shooting. Started with IMR 4198 & 87 gr. bullets, but case got full (compressed load) before maxing out. Went to RL 7 or WW680 for better results in shorter bbl from the Lyman data.
Newer powders, not much info, as the 256 is considered obsolete. Lyman 45th has data for both rifle and pistol with usable powders at the time, same with Hornady, and they will work good. Since you say you have lots of 4198, go for it.
If you are using in a Marlin M62 rifle, a friend had one but it had a large chamber like the T/C and brass was really worked when resized. Not good for brass life. Something to pay attention to.

 

[Hohn]

General rule of thumb: if a recipe for an older round calls for a powder with both IMR and H versions, it means the IMR version. H versions of the powders are generally much newer formulations that didn’t exist when old data was published.

 

[ebb]

Try both at a safe starting load. When working with a 6.5-284 I tried IMR4831 and H 4831 and the IMR shot better with some bullets. H4831 shot better with others.