.357 Magnum: 4" vs 6"

Discussion in 'Reloading' started by Highspeedlane, Jun 22, 2012.

  1. Highspeedlane

    Highspeedlane NRA Life Member

    I shot and recorded these loads a while back, but lately have gotten a hankering to shoot more .357 and figured it wouldn't hurt to post these results.

    The 4" barrel - S&W 686

    The 6" barrel - Ruger Security Six


    There is a dramatic difference in velocity with slower powders, and particularly when the charge weight is higher (and correspondingly bullet weight lighter).

    First load:
    Rem 158 grain JHP / 16.2 gr H110 / R-P case / CCI 550 primer

    4" barrel average velocity - 1225 fps
    6" barrel average velocity - 1360 fps

    Second load:
    RCBS 150 gr cast SWC GC (cast in linotype, average weight 145 grains) / 16.8 gr W296 / R-P case / didn't record primer but probably CCI 550

    4" barrel average velocity - 1223 fps
    6" barrel average velocity - 1455 fps

    Third load:
    Remington 125 grain JHP / 20.5 gr W296 / R-P case / CCI 550 primer

    4" barrel average velocity - 1464 fps
    6" barrel average velocity - 1658 fps

    On load three, the load is mildly compressed and there is moderate deformation of the soft lead nose during bullet seating. Any more powder than that (and there is more room according to Hodgdon) and the nose is severely deformed.

    The recoil of load 3 is significant for the middle weight .357 revolver and the 4" 686 definitely handled it better. It's almost nasty in the slimmer, less muzzle heavy Security Six.

    Below: a night shot with the 4" 686 using a 110 gr JHP over a hefty charge of W296.


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  3. Zombie Steve

    Zombie Steve Decap Pin Killa

    Always interesting to see the numbers. I always wonder how much is barrel length, and how much is the difference in cylinder gaps.

    Thanks for posting it up...

  4. Highspeedlane

    Highspeedlane NRA Life Member

    Thanks Steve

    I haven't measured the gaps but based on calibrated eyeball I'd say the S&W has a very slightly tighter gap, but not by much.

    The big takeaway for me is that there is a good deal of difference in these two barrels with respect to velocity, but from a recoil perspective, the extra weight of the S&W due to its underlug makes a noticeable difference.

    That load 3 is NASTY!
  5. WiskyT

    WiskyT Malcontent

    I had a pile of 357Mag data that got lost in my move. I have some data that I shot more recently that I will post later.

    One that was lost, that I remember well enough for our purposes, was 8.3 of Bullseye with a 125 JHP doing 1325 out of a 4" GP100.
  6. Zombie Steve

    Zombie Steve Decap Pin Killa

    I don't cotton to the 125's for that reason. Just an unbearable flash and blast. On the other end of the spectrum, the 180's just lose too much speed in the 4" barrels I shoot. 158's seem just right for me.
  7. Highspeedlane

    Highspeedlane NRA Life Member

    Interesting stuff. I've never taken Bullseye to that level.

    I need to get a GP100 some day.
  8. Highspeedlane

    Highspeedlane NRA Life Member

    What I notice is touching off that much slow powder in a .357" bore produces a very noticeable orange fireball. I set off more W296 than that in a larger bore and never notice it.

    The 158's are well balanced for the .357. I'm afraid if I ever had to touch off load 3 indoors in any sort of self-defense scenario I'd become a lifetime customer of Miracle Ear.
  9. Hi guys, interesting stuff. Back in the 80's I started loading everything with Hercules Unique. After Alliant started making the Unique I switched my other calibers over to other powders, but I have kept on loading the .357 with the Unique. I have a Ruger GP100 with a 6" barrel.If I remember right my standard load of 7.8 grains of Unique behind a 158 grain bullet got me around 1250 fps from that 6 inch barrel. I've also got a SP101 with a 2" barrel and I never really thought about how many fps I'd be losing out of the shorter one. I can tell you my wife loves shooting the GP100 with those loads. I did put a Hogue grip on it.
  10. WiskyT

    WiskyT Malcontent

    The results were less than spectacular. My buddy put a cylinder full of them in his SW 19 and the cases were hard to extract and had b ulged a little in the extractor area at the base of the case. It was the max load in the Hercules booklet back when they listed every powder in every caliber (pistol).

    But back then, all I cared about was making noise. For 125's at max velocity, medium powders work much better. The small increase in velocity from slow powders isn't worth the flash and noise.

    Max effort loads in 357 do much better with 158's as you said. 158's can go almost as fast as 125's and are better penetrating air and everything else. A cast 158 with Lilgun out of a 6" gun is doing 1500+. I have to reshoot my Lilgun 158 loads out of my 6 5/8" Blackhawk and see how they do. I did them indoors and the flash was affecting the chrono.

    Heavier bullets may do even better than 158's, but I never played with them.
  11. WiskyT

    WiskyT Malcontent

    Here's some data. None of these loads should be assumed to be safe. I could make a typo, or I might just be a nut, you never know. Verify all load data through published sources before trying any of it in your guns.

    4" GP100
    125 grain Master Match JHP
    Black Hills case
    9.7 grains WW 540
    Low: 958.9
    High: 985.9
    Average: 969.2
    Extreme Spread: 27.02
    Standard Deviation: 9.79

    This was a max load listed in whatever source I used. I've seen 38 Specials that ran faster than this. There was so much unburnt powder that it would foul under the extractor star and tie up the gun. I have half a box of these left and I'm too lazy to pull them and too lazy to shoot them. The powder has been discontinued. I think the data was the problem. If the data was developed properly, the load would have run faster and there wouldn't have been a teaspoon of unburnt powder left in the gun after each cylinder full.

    4" GP 100
    125 Master Match
    15.7 Blue Dot
    Winchester case

    L: 1518
    H: 1596
    A: 1561
    E: 77.92
    SD: 25.67

    Fast, clean, lots of muzzle flash. Alliant now warns not to load 125 grain bullets in 357Mag with Blue Dot. Go figyah.

    4" GP100
    19.0 Lil'Gun
    Winchester case


    Low flash, excellent accuracy, stiff recoil. I couldn't chrono it out of my SP101 because the trigger guard rapped my middle finger knuckle so hard I couldn't fire more than two shots. This load is slightly higher than the max listed on Hodgdon's web site.
  12. WiskyT

    WiskyT Malcontent

    Here is a good couple of loads to illustrate how much changing one component can change results. Both loads are the same powder, primer and case. Both loads were loaded from the same bottle of powder and box of primers. Both loads were shot from the same 2.25" SP101 on the same day. The only difference is the bullet. The Lee bullet takes up less case volume than the Lyman bullet.

    158 grain Lee RN weighing 160 grains
    14.7 2400


    Lyman 358477 150 grain SWC weighing 155 grains

  13. WiskyT

    WiskyT Malcontent

    This is a good load for all around use. It's cheap to make, easy to shoot, accurate, and out of the SP101, almost as fast as the full power 2400 load posted above:

    2.25" SP101
    Lee 160RN
    7.0 Unique

  14. FLIPPER 348

    FLIPPER 348 Happy Member


    I keep my 296 down to 15.3 or so for the 6" revolvers and rifles as any higher is just noise, flash and recoil. I do like my Blue Dot loads to be thumpers though!
  15. This stuff brings back memories! Back in the late seventies when my bud and i began loading our own 357's on his pop's coax, we used 8 grains of bullseye with a 125 jhp. We both had 2 1/2 inch smith 19's. Mine handled the load ok, but the primer would flow into the firing pin hole in my bud's, tying the gun up sometimes. We went to 2400 soon after.
  16. Highspeedlane

    Highspeedlane NRA Life Member

    Thanks for all the contributions...interesting info for sure.

    Back in 1982 I enlisted in the USMC. The recruiter came over to my house one day before I left for lovely PI and brought his stainless Security Six with a 6" barrel.

    At the time, my Security Six (totally coincidental we both owned one!) had a 2-3/4" barrel. We loaded up some Hornady factory 158 grain JSP and took aim at an old junk industrial electrical panel.

    I'm not sure how thick the metal was on the panel but from about 20 feet away my 2-3/4" barrel just put deep dents in it, while using the same ammo, his punched right through.

    I was a little dismayed to say the least (me having no knowledge at the time of the effects of barrel length and velocity), and that incident lead me to sending my 2-3/4" SS back to Ruger to have a 6" tube screwed on.
  17. Interesting but unless it's the same gun & cutting the bbl, it really doesn't tell much. I have 5 diff 4" 357mags, they all have varying vel with identical loads, some as much as 100fps+. Cyl gap, chamber size, groove dia, bbl smoothness, it all matters for vel.
  18. Highspeedlane

    Highspeedlane NRA Life Member

    Thanks for all your input Wisky.
  19. Highspeedlane

    Highspeedlane NRA Life Member

    +1 on that Fred.
  20. FWIW, every Ruger I have run over a chrono shoots faster than other manuf. I had a Ruger SS 2 3/4" that was as fast as most 4" guns. Tighter specs I would imagine.

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