Quantcast

Max Velocity on 5" 357 mag

Discussion in 'Handloading and Reloading' started by 98s1lightning, Nov 10, 2019.

  1. Walkalong

    Walkalong Moderator Staff Member

    Joined:
    Nov 20, 2006
    Messages:
    59,983
    Location:
    Alabama
    All guns are, but yea, it's bad. Protect your hearing, you can't get it back, just ask the old time shooters.
     
    Bfh_auto likes this.
  2. forrest r

    forrest r Member

    Joined:
    Oct 6, 2016
    Messages:
    410
    I don't keep those revolvers around long anymore. Too many more of them out there along with I just don't want to fix/replace cylinders/bbl gaps/bbl.'s anymore. There's something to be said for dan wessons.

    There's a lot of experience with MP-300 on this website, their advise is spot on. Last year I did testing with different 35cal bullets and a little head to head testing with 2400/MP-300/H110.

    Typically there's huge differences in velocities between plated/jacketed/cast/coated bullets. Add to that the bullets design itself will play a huge role in getting the most velocity out of a given load/revolver combo. I used these 8 bullets along with 2 hollow based bullets not shown in pic.
    0A0Ga7O.jpg

    I used 5 different powders for the bullet tests, along with 1x brass, hot primers and max p+ loads with heavy roll crimps in a 2" bbl'd snubnosed 38spl revolver. You wouldn't think that a bullets design would make any real difference in velocities especially with a 2" bbl. At the end of the day the cream rises to the top & after a 500 round/10-bullet test these 4 bullets consistently outperformed the other 6 bullets.
    vlZBK9y.jpg

    The bullet 2nd from left is a cast 148gr hbwc that was turned/loaded backwards. These bullets outperformed other bullets by as much as 70fps & while 70fps doesn't sound like much. The difference between a 158gr bullet doing 850fps and 920fps in a snubnosed 38spl is huge. These bullets outperformed the others because they had the ability to seal the cylinders/bbl quickly/more efficiently with their large bottom drive band (cast) and the long bodied home swaged bullet (right).

    I decided to use the green bullet (top picture, top row 2nd from left) in testing 357 in different bbl length 357 revolvers and a 10" tc contender. It was +/- 20fps slower then the bullets in the bottom picture/38spl test. I chose that 158gr mihec 640 hp to test in the 357's because I can cast a 170gr fn bullets by simply changing pins in the mold.
    3f3FUJ4.jpg

    I was looking for a 1200fps+ load for a 2 1/2" bbl'd s&w 586 l-comp. S&W lists the 586 l-comp as a 3" bbl'd revolver. That to know what holsers to look at, the revolver itself has a comp at the end of the bbl' shroud and the revolver really only has a 2 1/2" bbl. So I loaded up a bunch of full house loads using 2400/MP-300/H110 and that 158gr hp bullet pictured above. The bbl lengths used in the test was:
    one 2 1/2"
    two 4"
    two 6"
    one 8"
    one 10" (tc contender)

    While not doing a lot of test loads because this was the initial/1st/beginning tests with those bullet/powder combo's. I ran 20-shot strings in each firearm/bbl (used a dw 15-2 with the 4"/6"/8" bbl.'s).

    In the 2 1/2" bbl the 2400 load outperformed the MP-300 & H110 by +/- 50fps and did 1200fps+ (I was looking for a 1200fps load in that 586)
    In the 4" bbl.'s all 3 powders were about even doing 1300fps+
    In the 6" bbl.'s the MP-300 & H100 started to pull ahead of the 2400 with the MP-300 & H110 doing 1450fps+
    In the 8" bbl the MP-300 & H110 really started to shine doing 1510fps+
    The contender did 1620fps+ with both the MP-300 & H110

    I really couldn't tell much difference between the MP-300 & H110 loads, they were within 20fps of each other throughout the entire testing. I'm sure that a different bullet (1 of the 4 pictured above) would bring out the most with the MP-300 & H110 loads.

    With careful bullet selection, excellent neck tension and heavy crimps I see no reason the op couldn't get in the +/- 1400fps range without too much effort. After that everything counts.
     
  3. jmorris

    jmorris Member

    Joined:
    Sep 30, 2005
    Messages:
    13,883
    That assumption can only be made within a given burn rate window.

    There are some powders that burn so fast, that a case full of it would blow up the firearm vs make a big fireball out of the muzzle, like a slower powder would.
     
    Bfh_auto likes this.
  4. jmorris

    jmorris Member

    Joined:
    Sep 30, 2005
    Messages:
    13,883
    Yep, they can fix your eyes, heart and lots of other stuff. You mess up your ears and your stuck on Internet forums to communicate with people. :)
     
    Bfh_auto, Walkalong and 98s1lightning like this.
  5. RealGun

    RealGun Member

    Joined:
    Mar 21, 2004
    Messages:
    8,384
    Location:
    Upstate SC
    MP-300 is a great load using Hornady XTP data, but I was challenged finding load data for using 300-MP with lead, a story similar to H110/W296. The magnum powder that has wider support for lead is IMR4227. I stuck a bullet in my 629 trying to extrapolate from jacketed data, namely discounting the Alliant max number for jacketed and then for minimum. I set the 300-MP aside for years until using it on needing some XTPs and finding it to be my favorite jacketed 44 Mag load when not downloaded or by much. I would expect similar results with my .357 Magnums, which I don't often shoot full power.
     
  6. WrongHanded
    • Contributing Member

    WrongHanded Contributing Member

    Joined:
    Jul 6, 2017
    Messages:
    1,332
  7. RealGun

    RealGun Member

    Joined:
    Mar 21, 2004
    Messages:
    8,384
    Location:
    Upstate SC
    Yes, thanks. I followed that tip some years back and have the magazine issue. I could have used the data in .357 Magnum, but shied from those velocities because of a concern about leading. My attempt to use the powder was in 44 Mag until recently. I should have just gone with jacketed or GC, which is what I do now with MP-300.
     
    WrongHanded likes this.
  8. crestoncowboy

    crestoncowboy Member

    Joined:
    Feb 22, 2011
    Messages:
    1,342
    My 329pd shoots the same ammo faster than my PC model, 629, older 29, or my 7 (and 1/2 or whatever ruger called it) inch Redhawks all with longer barrels. And nearly what the 10 inch blackhawk shoots. It also shows pressure signs far faster than all the rest. So individual guns certainly vary. I think more so with revolvers than semi-autos because timing of each chamber and cylinder gap/forcing cone differences etc.
     
    Walkalong likes this.
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice