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357 Mag Loading Help

Nimitz9Nimitz9 Member Posts: 9 ✭✭
357 Mag loading is kicking my rear. I loaded some 158gr semiwadcutters with Alliant 2400, leaded the heck out of my barrel. Cleaned barrel and loaded 158gr sjhp with Unique, pressure so high the brass was really sticky and primers flattened. Unloaded 44 rounds made with Unique and bought W296. Used regular Winchester small pistol primers and the recommended load but oh my, what a flame. The range officer asked me if it was a 454. Cases slid out just fine, primers a little flat but not more so than boxed ammo - but still makes me nervous. The W296 also jammed up my powder measure on my Dillon. Disassembled the powder measure and cleaned all that up so now I am ready to try again.

So two questions:

What powder do you 357 Mag guys like?
If you have experience with W296 is it supposed to roar that much?




  • BHAVINBHAVIN Member Posts: 3,490 ✭✭
    edited November -1
    My family has used 7.0g of Unique with 158g jacketed or JHP and small pistol primers for over 40 years with great luck and used Unique for leads for alot longer than that. Make sure your cyinder is clean and that there isn't a ring from shooting 38spl loads. What did you use for a powder charge with Unique? The only drawbacks with Unique is that it is very temperture sensitive when measuring and it is dirty compared to newer powders like Titgroup. 2400 for higher end 357 loads works well but is on the dirty side. I have bever used W296.
  • dtknowlesdtknowles Member Posts: 810 ✭✭✭✭
    edited November -1
    I use H110 with 125 gr. JHP's, I feel is this is a good option for mid to long barreled revolvers, high velocity for flat trajectory and good expansion, lots of foot pounds. I have used Unique with heavy lead bullets with gas checks and not had bad leading. The lead semiwadcutters are pretty potent too, lots of pentration.

    Started using H110 recently and have not noticed any problems. Have used Unique for many years in a few guns, no problems with it either.

  • MrOrangeMrOrange Member Posts: 3,012
    edited November -1
    Sorry I can't give more help, but I've loaded mucho .38/.357 rounds with Unique, simply because it was Unique and I could use it for both of those, plus several other handgun rounds and shotshells.

    I know there's better stuff out there if you're looking for max hunting loads. I hope you've got a loading manual and are sticking to published loads? There's a reason they tell you to start 10% below max listed when looking for top-end loads, as every gun is different & what might work fine in mine could cause stuck cases in yours.
  • dclocodcloco Member Posts: 2,967
    edited November -1
    Hmmm...I just came in from sizing 400 rounds of 357 Magnum.

    I use Hodgdon HS6 or HS7 with CCI Magnum Pistol primers. I load it on the low end (the range is 8.5-9.5 grains of HS6).

    You have something going on should not be flattening primers or sticking brass.

    I have to ask, is the cylinder clean?

    How many grains of each powder are you using???

    From Alliant's website, using Fed 200 primers:

    1.575 5.6 Fed. 200 Unique 7.8 1,280 33,200
    1.575 5.6 Fed. 200 2400 14 1,295 32,500
  • PearywPearyw Member Posts: 3,699
    edited November -1
    I have loaded 357 a lot with W296. It is a slow burning powder and will produce a good bit of muzzle flash. It should be used with magnum primers. I only use it if I want the highest velocities. Cast lead or swaged lead bullets will lead barrels if you go over 1000fps load. If you want to you lead bullets for full power loads, they need to be hard alloy with a gas check. W296 is bad to jam up powder measures. It has some pretty fine powder in it that tends to jam things. I use a lot of H110 that seems to meter better. 2400 also meters well.
  • 11b6r11b6r Member Posts: 16,725
    edited November -1
    Like the man said- soft lead bullets+ no gas check+ high velocity= leaded up bore. For LEAD 158 gr SWC, 5.5 to 6.0 gr of Unique, or 4.3 to 4.8 gr of Bullseye. For 158 gr SEMIJACKETED- 7.7 to 8.2 gr of Unique, 15.8 to 17.8 gr of 296 WITH MAGNUM PRIMER. I use Bulleye and Unique quite a bit- between the two, I can load durn near any pistol caliber. Yeah, they are dirty. Got a bottle of Hoppes? Above loads are from Speer Manual #10. Find a good reloading manual, and stick with the loads. The folks that tell you that "book" loads are wimpy because of lawyers are idiots- they spent time researching those loads for good reasons. You will also find that hottest load is also usually not the most accurate load. Shorter barrel will equal more muzzle flash, all other things being equal. Once shot some 95 gr +p 38 Specials in a 2 inch Mdl 36- thought the range had caught fire- ball of flame at muzzle 3 ft across.
  • Nimitz9Nimitz9 Member Posts: 9 ✭✭
    edited November -1
    Thanks all for the replies.

    My Unique load was 125gr Rem. JHP, Federal small pistol primers, 9.5gr of Unique, mixed cases (I had measured them all, all were nickel plated and mostly Winchester but some Federal) and a fairly heavy crimp. Measuring crimp is something of an art to me. I had tried 9.0 grains and all seemed well, tried some at 9.5 grains and when that worked ok I went for making 50 rounds. It has been a couple of years so I don't remember all the details really well, but there were about 9 months between the testing and when I found the excessive pressure - so several things probably changed including the amount of crimp. My Alliant reloading guide says 9.6 grains of Unique is max.

    The W296, which I think is the same as H110, is a great powder and makes a manly magnum. I shot up a bunch of them in my Blackhawk and it is the real deal. The shells fall right out of the cylinders too. My Winchester guide warns about reducing the load and says to use Winchester small pistol primers - I thought about going to magnum primers because there is some unburnt powder when I am done, but I went with what the guide said.

    Normally I just shoot 38's made with W231 (comment about cleaning is a good one, thanks, in this case I had cleaned all the cylinders and barrel well because I was trying for accuracy).

    I am leaning toward 2400 powder for the next round but will use jacketed bullets. I will try some more of the W296 but will load these more like rifle rounds using new brass and will weigh each powder charge.
  • 11b6r11b6r Member Posts: 16,725
    edited November -1
    Well, you usually won't go wrong following the book- especially the part that says WORK UP TO the max load. And if you change any one component- bullet, powder, primer, case- back off and work back up. The manual I keep on my desk list 9.1 gr of Unique as max with a 125 gr Jacketed bullet. Not saying yours is wrong, just different.
  • bpostbpost Member Posts: 32,449 ✭✭✭✭
    edited November -1
    Blue Dot for JHP loads are very good.

    I have shot about 30,000 rounds of .357 loaded with 6.0 grains of Unique and a 158 grain cast plain based Keith style bullet.

    It is my favorite .357 mag. plinking load.
  • CubsloverCubslover Member Posts: 18,601 ✭✭
    edited November -1
    Offhand I remember using 16.4gr H110 behind a 158 SJHP.
    Half of the lives they tell about me aren't true.
  • MatchshotMatchshot Member Posts: 452 ✭✭✭
    edited November -1
    Here's one more suggestion, from a friend who has gotten me into reloading and has a ton of load data:

    158gr JHP 10.5gr. AA#7 WSP primer 1.570 1100 fps
    Moderate Load, Moderate Crimp, 1.75" in M586 & M19,
    2.25" in GP100, 2" in Blackhawk, 1" in Nickel 586
  • GUNFUNCOGUNFUNCO Member Posts: 2,920 ✭✭✭
    edited November -1
    My favorite load for the 357 is 14 grains of 2400 with a speer 158 grain jacketed soft point or hollowpoint and CCI 550 magnum primer. Very accurate.

    Also, I usually try to have the chambers in the cylinder dry, with no oil residue. I run a dry patch thru them before shooting to remove any traces of lube. I do this so that when the case expands, it doesn't slip back against the recoil shield with as much pressure.
  • glabrayglabray Member Posts: 679 ✭✭✭✭
    edited November -1
    I second the use of 14 or so grains of 2400. Works great in all my 357s. At the risk of having Elmer turn over in his grave, I have to say that I have never gotten what I consider good accuracy with a semi-wadcutter bullet in an out-of-th box revolver. Unless the chamber-to bore alignment is dead-nuts perfect, that abrupt bullet shoulder gets distorted on one side throwing the bullet out of balance.
  • HKmanHKman Member Posts: 291 ✭✭✭
    edited November -1
    Here's one for ya.

    Speer 147gr. JHP
    WSP primer
    HiSkor 800-X (IMR) 8.2gr
    OAL 1.565"
    VEL. 1200 fps + or -[}:)]OUCH!!!
    Just over 35,000 p.s.i.

    Have fun and good luck!!!
  • ironsightironsight Member Posts: 13 ✭✭
    edited November -1
    Win 296 is a very slow burning powder that should be used with a magnum pistol primer. Start by reducing the max load in your load book by 10% and working the load up by a grain or so until you are getting uniform pressure. I have used a S/W .357 Mod. 686 for hunting hog and deer for years with a load of a 140gr. Serra hollow point over W296 and CCI magnum primer. It is a great powder for all magnums. Ya, you will get a lot of flame at the upper ends of the loads you choose with it but I haven't found another powder that does a true magnum load better. The others are correct in saying for any loading with a soft lead bullet over 1000fps, you need a hard cast bullet and a gas check. Otherwise, your barrel will become a lead pit! And even with the above combo, it will still lead some. Rule of thumb, higher velocities mean jacketed bullets. Keep those soft lead bullets for the 38 special loads at 800 - 900 fps.
  • kraschenbirnkraschenbirn Member Posts: 70 ✭✭
    edited November -1
    My favorite .357 load probably falls into the "oldie but goodie" bracket: 15.0 gr of IMR4227 behind a cast 158 gr SWC (Lyman #358156) w/gascheck and Fed #205 (Mag-Sm. Pistol) Primer. Have shot this load in S&W M28 and M586, Ruger Blackhawk, and 10" T/C Contender with no significant leading or signs of excessive pressure. Load chronographs at around 1280 fps (6" barrel) and is quite accurate; consistently printing 1 1/2" (or less) 5-shot groups at 25 yards (shooting off sandbags with an Aimpoint) from my 6" M586.

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