... for a .358 Winchester with a 19" barrel, shooting 220-grain Speers and 225-grain Partitions? How do I reach this target (load)?

The rifle is a M-600 Rem. Rebarreled from .243 to .358.

2200 to 2400 is about the range of velocity, however accuracy is usually paramount for me and velocity is second.
I hear 358 Wins like IMR 4320 so if it was me I'd start at 43 grains and work my way up in .5 grain increments to an accurate load and not be concerned with the speed.
Consult a reloading manual, Sierra is my favorite.

IMR 3031 is another great powder for the 358. Start at 42 grains and work up. I think 2450 fps should be doable.

I used H4895 in mine, with its 22" barrel I never got to 2400 fps with 220 Speers. Hodgdon's max loads with Varget reach 2445 fps...in a 26" barrel. I think that 2400 fps in a 19" barrel may be tough if the OP wants to load to safe SAAMI pressures.


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H 4198, Varget and W748 are my goto powders for my 358. I don't usually load the heavy bullets but for your 220 grain bullet use 38 to 41 grains of H4198
48 to 52 grains (compressed load) with W748
and 46 to 50 grains of Varget (compressed load)

You can also use H4895 at 43 to 47.5 (compressed load)

I stay away from compressed loads with W748 as it is a double based powder and there used to be all kinds of warnings about compressed charges. It is a decent powder - especially with the lighter bullets. 4895 has been a great choice since it has such good ignition properties. I have only recently started playing with Varget and it seems promising but I haven't gotten the accuracy from it yet that I got with other powders.

I would truely love to be able to reach 2400 fps, but I don't see it happening with 19 inches. Whatever I'm able to achieve will surely work better on game than the 100-grain, .243 bullets launched from the 18" factory barrel the rifle came with. I bought the gun way back in the early '70s when it was illegal to hunt hogs in Georgia (except during deer season) with any center-fire rifle over .25 caliber. The reason for that law was so game wardens could catch deer poachers hunting after the season had expired and they couldn't claim they were hog hunting. I guess the state figured .243s, 6.5s, etc., were not viable deer rifles. (Technically, .25-'06s and .257 Roberts were illegal since they were above the .25 caliber threshold -- which didn't matter much since no one in the state owned one! )

The 358 owned never reach the vel that some claim they were always a couple hundred feet slower.

I would bet dollars to donuts that you will lose at least 100 FPS and probably more, but that ain't much..The problem is I can toss rocks faster than the .358 shoots 250 gr. bullets! Just kidding, its a great hog and deer gun in the thick stuff, even elk in the shintangle.