[1858rem]

i got a lb of h-4198 for cast bullet/plated loads in 30-30....
and shortly i may be acquiring a m77 .204 AND a rem 788 .308.....
i see some data foe the imr 4198 and none for h 4198...
although they are one on top op the other on burn rate charts, imr is a bit slower i guess....

could i reduce loads of h4198 to substitute in for imr4198 most likely ONLY for the .308 and 30-30 though, i got some varget for the 204lol.

mostly im wondering how close to being interchangeable are h4198 and imr4198....:confused:

[Wil Terry]

..........

[NCsmitty]

I heard rumors months ago that Hodgdon was considering the dropping of their H4198. I still see it on my dealers shelf though.
Hodgdon has load listing for my 222 and there is a definite difference in charge weight and pressure listings between the two, with H4198 being a little slower in burn rate.
You be the judge and make the call.

NCsmitty

[1858rem]

i had seen somewhere that Hodgdon produced both.... but i could not understand why they were listed in the same loads... or even close, for the 30-30 could i just start 3-4.5g(10-15%) under max for imr4198 since its data is more readily available to me?

[Jim Watson]

Hodgdon doesn't produce anything (except Pyrodex.) They import and distribute IMR powders from Canada and their own brand from Australia. (Spherical powders are from St Marks Powder in Florida.)

DuPont originated IMR 4198 many years ago.
Hodgdon has ADI in Australia make a reasonable copy but they are not interchangeable at the top. Reduced loads for cast bullets, they are probably close enough.

[rcmodel]

Hodgdon probably has powder bunkers full of H-4198 from years ago production. Hard telling what you got without them telling you what the lot# represents.

I would use H-4198 data for H-4198.
And IMR-4198 data for IMR-4198.

But like already mentioned, they will be close enough for cast-bullet reduced loads.

rcmodel

[NCsmitty]

1858rem, if you go to the www.hodgdon.com site and get to the 30-30 data, you'll find a load for H4198 with a 160gr cast bullet. Got a Trailboss load too.

NCsmitty

[steve4102]

Current production totally interchangable as hodgdon's owns imr.

Nope, not interchangeable at all. I have both and use both and I can tell you that they do not load the same, look the same, shoot the same, have the same velocity, same accuracy. The only thing they have in common is the name.

[ArchAngelCD]

Just because the numbers are the same doesn't make the powders the same. I wouldn't interchange any data unless Hodgdon/IMR/Winchester tells you they are the same powders. (like W231/HP-38, W296/H110, W760/H414 and a few others)