Honestly it doesn't matter a whole lot what weight the bullet is then. Look at what is available, and shoot for the middle of the weight range.
It will be plenty for anything hiding in the woods in your part of the world.
There is a ton of 357 ammo available out there. For plinking, I would try and find some 38 sp. +P in the 158 gr. SWC. I have shot a bajillion rounds of it in mostly Winchester brand or handloads, but I'm sure others make it. That same weight jacketed bullet in 357 Magnum should also do you well. Probably more brands out there than you can sort through. I even see that Fiocchi is manufacturing it. I have been impressed with the Fiocchi shotgun ammo over the last several years and actually picked up some in 22-250 that shot quite well.
Federal used to make some pretty peppy Magnum ammo back in the day, but not sure about their offerings nowadays.
Not having anything specific in mind ... most ammo selection being depends on the target...
A good all around choice would be in the 158 grain weight .
158 grains has been the sort of standard for 38 special and on to 357 Magnum .
It's sort of Goldilocks ...not too heavy and not too light .
38 cal bullets run from : 110 gr. , 125 gr. , 140 gr. , 150 gr. , 158 gr. , 160 gr. , 170 gr. , and 180 gr. . The 150 gr. , 158 gr. or 160 gr. weights would all do for most general purpose shooting .
But with the ammo supply situation being what it is ... buy whatever you can find !
Bullet WEIGHTS are one consideration, but bullet SHAPES are another. I like the LSWC for many applications in revolvers, but they often do not feed well through lever-action rifles. The flat nose and sharp shoulder features that make them so desirable for defense and hunting will often hang on sharp and unpolished rifle action parts.
The last time I piddled with a .357 Mag lever action, it was a Marlin, so this may/may not work in a Henry. We found that the Sierra 125 gr. and 158 gr. JSP bullets, despite the flat nose and exposed lead, fed best through that rifle's action. Bullets of this particular geometry actually fed better than various Jacketed Hollow-Points with more rounded points, and no exposed lead.
Your best bet is to try various SHAPES of bullets to see which ones feed smoothly and rapidly through your rifle's action. This is FAR more important than terminal effect, if you intend to use this rifle to preserve your life. I personally like projectiles weighing 125 gr. and more, for defense and game-getting, but if the only projectile that fed through my lever-action .357 Mag. weighed 110 gr., I'd use it unreservedly. In the Henry, I suspect that you won't have this trouble, if you avoid bullets with sharp shoulders, a la LSWC.
Once you have found a group of projectile types that function well, spend some time testing for accuracy. Your rifle will like some weights better than others.
If memory serves, a lever action .357 Magnum carbine can launch a 125 gr. projectile at or slightly over the muzzle velocity of a .30 U.S. Carbine. With 14% more bullet weight and much better bore area, this makes your rifle a fair proposition for white tails under 100 yards, and "two-legged vermin" at any range at which you are likely to connect.
Congrats on your new rifle and good luck!
There is some really good advice given above. I used two Rossi lever actions years ago in .357 and .38 My preferred loads were 158 hard cast lead SWC in both .38 and .357 around 1000 fps. Serious loads were a Speer 140 gr HP using max loads of Win 296 and mag primers. That Speer load hit like a thunderbolt and was devastating on anything under one hundred pounds. All loads fed and functioned very well.
A forum community dedicated to Sport shooters, owners and enthusiasts. Come join the discussion about optics, hand casting bullets, hunting, gunsmithing, styles, reviews, accessories, classifieds, and more!