Rich, where did you find the loading using 231, and what fps does it give? Yes, the 296 is a ball powder. Different powders from different manufacturers will be different sizes, but there shouldn't be that big of a difference unless it's a low power load, like a .38 special range load. Are you sure that 231 listing isn't for the .38 special? Not that will matter in that gun. The .38s can be safely shot in a .357 gun. But not the other way around.
I can't find a load using the 231 in a .357 magnum in any of my books, but the 231 is listed for the .38 special. That's why. What is stamp on the bottom of the cases you are loading? Does it say .38 or .357? It will work fine with what you are doing but it will be a much less powerful loading.
One thing that people like about powders that will fill a majority of the case is it's very obvious if you double charge the round. You don't want to double charge the round, ever. It could easily cost you a gun, some fingers, maybe a hand, or worse
My Load data come from Hogden load data website. (pic attached)
158g HP bullet, .357 magnum Winchester shell, SPM primer, W231 powder. (6.2 - 6.9)
I did shoot it and it fired in both guns flawlessly, but it was certainly lighter than the Magtech factory ammo I compared to. (the starting load of 6.2 was especially friendly)
I went back and loaded up to 6.8g and compared - much better and pretty equal to the Sellier & Bellot factory ammo, but still not as heavy (recoil) as the MagTech
Both factory ammo's are 158g bullets, one a flat tip and one a HP. The Magtech is the HP and it definitely kicks more than the Sellier and more than any of my loads. (I put two of mine, two of the Sellior, and two of the Magtech rounds into my Ruger 6 shooter and compared shooting them.) Then I tried them in the Henry. I could certainly tell the difference
I went back to the Hogden site and entered 296 and it does say 15.0 - 16.7g for the 296 (1418-1591 fps)
The 231 at these loads is only throwing 1108-1220 fps so I will try some other powders. (The 231 is all I have at the moment). I looked for True Blue and 296, but haven't found them yet.
(and I do not have a chronograph...yet, so I can't measure the velocities)
I actually found a used Hornady Load book at the used book store late Saturday, but I have not checked it yet (not sure what wifey did with it when we got home). I have a 2020 Hornady and a new LEE book also on the way, but don't have either in hand yet.
Also, not sure how much if any difference, but I'm using X-treme plated bullets (158gr HP), but I believe as long as the weight & shape is the same...it's fairly uniform, as long as length, etc is all the same. I have a X-Treme's load data manual, but it only shows three powders (Power Pistol, Hogdon CFE, Vihtavhuori N-110)
Also, I have a progressive press so double charges would be difficult and I am being extremely careful. I do have a powder cop die (visual cue check), but I'm still looking for a Lee lockout die, but they are all sold out everywhere I've looked online. I am overly cautious and check the powder weight every 10 shells or so and before and after the 1st and last full cartridge just to make sure. I'm impressed the powder drop is as accurate as it is. So far, so good.
Pretty happy with the loading project so far...getting the press set up and tested some loads (and still have all my fingers...and guns intact) Glad I went ahead with the progressive (Hornady AP) for my needs. Bit of a longer learning curve, but once you get the dies set it pretty darn efficient even with a rookie.
I've noticed some flaws.. well not flaws - some thoughts on using the stations. I'm hand de-priming my old shells rather than on the press. (I have not used any old shells yet, but...) IF I followed the press setup, station one is resizing and de-priming, (priming is between 1&2) station 2 is expander, 3 is powder drop, 4 is seating/crimping. (all my dies are TC dies so far).So basically, IF you are depriming on the press and resizing and then ...Well then you are not cleaning the primer pockets on the brass. (assuming you are case prepping after cleaning, and before de-priming)I plan to use a bullet feeder tube eventually, so that will take up a station, and IF I ever find the lockout die, that's another (which will require I use the powder thru expander die...which I don't have yet so I can remove my expander die and use a lockout after the powder drop)I've read many folks saying cleaning the primer pocket is not necessary/critical for hand gun loads. What say you senior member?Also, what is your opinion on separate seating and crimping? Also read a lot of folks prefer to do them separately. (not that I have a choice with the dies I have so far)
Thanks for all the tips and advice.