Hi guys, I have had a lot of success recently using H4198 16gns in my .30-30, behind a 165 gn cast bullet. I am thinking about doing the same for my .308 WIN. The Lyman manual lists the same bullet with 24 gn of IMR4198!

Here in lies the problem, here I can only get H4198 and not IMR4198! Hodgdon listed a load for 160 gn cast bullets using H4198, they do not however list such a load for cast in the .308 Win. On the basis of extrapolation (case capacity, and a ratio between recommended H4198 (starting 15gns) vs IMR4198 (starting 18gns) for the 30-30) 16 gns in the 30-30 would be around 20 in the .308, but I don't want to just guess at it. Has anyone used H4198 in the .308 WIN?

I know IMR4198 and H4198 are not identical are they similar enough at reduced loads?

I use plenty of 4198 in a lot of calibers...
IMRs is more accurate across the board.. but still the load data for Hodgdon's is interchangable.. burn rates are close enough... unless you are trying to turn your 308 into a 300 Win Mag using the least amount of powder possible....

yeah, there are nuts who do stupid things like that..max load will be 33 grains or so if using a 180 grain bullet, or 35 grains for a 150 grain bullet..or 38 with a 110 grain bullet..

source, IMR's old Brown Sheet Load Guide.

Well said, Seafire