What Are "True" .357 Magnum Ballistics?

You can do a comparison of the .357 without leaving your computer. Simply download Accurate Arms 3.2 and 3.3 load data .pdf files. The V3.2 lists the old data, V3.3 lists the new. For a 158gr Hornady XTP, here's what you'll find...

Maximum load #9 powder...15.0gr, Velocity...1470 fps, pressure...44.900 cup
Maximum load #9 powder...13.8gr, Velocity...1367 fps, pressure...35,022 psi
 
A 125 JSP might be just the ticket out of a carbine. To keep it from exploding.
The SGD's are bonded so I don't think it would fragment anyway.
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I think you would have to do some experimenting. Its not just bonded or not, hollowpoint or not. Bullets that are designed to expand are designed (and made) to do so within a certain velocity range. When driven 30% (+/-) faster than they are designed for, results get ...atypical.

The regular 125gr JHP has become the premier self defense load in the past few decades. The bullet has become optimized for that, to work, and work well in the velocity range of regular handguns. Add 500fps to that speed, and change the target from a human to a deer or other medium size animal and you get radically different results, usually poor penetration and violently explosive expansion.

Bonded bullets are made to open up, and still keep together, but I think that there is also a velocity range that exceeds this capability as well. You need to test the bullet at carbine speeds to see just what will happen.

Some JSP bullets are the same as the JHP, just without the hollow point. Others might have slightly different(and possibly important) internal differences. I just don't know, so you need to find out, before you take to the game fields.

I do know that light JHP .357 bullets fired hundreds of FPS faster than handgun speeds do change their performance. SO do .30-30 bullets frired out of a .300 Magnum and bullets intended for expansion at traditional .45-70 speeds become varmint bullets when fired out of a .458 Win mag.

Its not east to make a bullet that will expand "enough" at the lower end of its velocity range, and not expand "too much" at the upper end. When you step outside that range by a quarter or a third, on the upper end, things no longer work exactly as designed.

In an imperfect analogy, the amount of sail that sends you along nice and happy in a 20mph breeze is the wrong amount to carry when you meet gale force winds.
 
44 AMP,

Excellent points Sir. A classic case of "more" not always being better. Some things don't magnumise well.

Dave
 
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I'm getting a big boom with 19.5 grains of 296 and a 125 grain bullet out of my Rossi 92 I back it off a grain for my 586. I'm going look for bigger bullets and less power and see if a bigger bearing surface helps the round stay tight out to 100 yards.
 
<<<Remember, the modern loads are tested in 10 inch vented barrels,and used in 3-4 inch barrels. Big drop there. >>>

Where do people come up with this stuff?
 
The original ballistics of the 357 Magnum in 1935 were 1512 fps with a 158 out of a 8 3/4" (note 3/4" not 3/8" as that came later) according to an original S&W late 1930's catalog.

The same advertisement lists 38/44 S&W Special ammo at 1226 with a 158 out of the same gun.

As a rough check, I have shot original 1930's 38/44 S&W Special ammo out of my 8 3/8" pre-27's and found it was running right at 1200 fps and 1150 out of a 6.5" 38/44 Outdoorsman.

My gut reaction is that original ammo would have done right about that range and S&W was not padding their velocities by much. I have not found enough original large primer 357 magnum ammo to run a statistically significant test though.

So for ease of memory, I quote the ballistics as 1515 FPS with a 158 out of an 8 3/8" 357 Magnum. If it is not doing that, then it is wimped down modern ammo designed not to overly stress a smaller framed gun.
 
My shooting buddy found that if he loaded 158 grain to a velocity hotter than 1400 fps, the cases were too tight to extract with thumb pressure on the ejector rod. We had to bang them out.

This was chrono measured in about 1990, using both a 6 inch Ruger security six and an L frame 6 inch smith. So 1400 was the hottest we ever loaded them. Even then, he wasn't getting a lot of life out of his brass.

At 1300 fps, it was a whole different story, the ejection was smooth and the brass lasted a lot longer.
 
but if you arent going to exploit the extra case length then is might not be as wise to shoot low pow true magnum when another true ammo could do task
 
When I loaded for the 357, using 2400 it was no problem getting a 158gr SWC hardcast to a little over 1500 fps from my (then) 6" Ruger GP100.

Try as I might I couldn't ever get the 158gr jacketed bullets anywhere near that fast, they would top out in the low-mid 1300's.
 
I think most 357 mag revolvers will take some loads much hotter than what you can buy off the shelf, one of my favorite ammo manufacturers Kevin Underwood, loads a 357 bjhp 125gr that flys 1700fps and goes over 800 ft lbs!!! I have shot and chrono'd that round on many occasions, its a beast, if you are looking for stopping power in a handgun.

For ccw http://www.smith-wesson.com/webapp/...75660_775655_757751_ProductDisplayErrorView_Y

or home defense http://www.smith-wesson.com/webapp/...75660_775655_757751_ProductDisplayErrorView_Y with a nice streamlight mounted...

BUT, I am sure it will take some practice to master the follow up shots, although if you get a hold of the first one, you probably won't need too many more to get the job done, I have shot water jugs with a lot of handguns, and when I use my 686 competitor {its a heavy girl, fully weighted} from 25 yards there is no other handgun I own {except my 460mag, but you are not grouping that gun in short order, I don't care who you are}} that makes the water fly like the underwood hollows..

Now that is just 16 rounds once and a while, I wouldn't want to shoot hot stuff for plinking, that would be defense ammo, I shake my head when I see these guys at the range shooting 1500fps ammo to pop wholes in paper for 2 hours, its expensive, beats up the gun, and the shooter, I run wadcutters and semi's, and some balls, loaded how ever I have the brass ready, some 38-s, 357, I do an array of it all, I have been using the same brass for a while, light target loads are much more fun to shoot than fire breathing mag loads..
 
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a 357 bjhp 125gr that flys 1700fps
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I have some experience with handloads in this range (see post#16), and I can tell you that MY loads in this range will NOT work in ALL .357s.

The N frame S&W (mine is a model 28) is a hell of a gun. Runs normally on ammo that is too hot for K frames, or smaller guns. I've even found some loads the N frame is fine with that are to hot for my T/C Contender, or even my Marlin carbine! My Ruger new model Blackhawk seems to be as tolerant of ammo as my model 28.

I will not shoot that stuff out of my model 66. Having to drive each case out of the chamber with a rod & small mallet means the load is too hot for that gun! Even if there are no other pressure signs.

I have no personal hands on experience with the L frame guns, or the Ruger 100 series. I did have a Security Six, and its no N frame, either.

Personally, I see no point to the S&W L frame guns, other then personal preferences. Overall weight is the same as the N frames (so, nothing is "saved" there) and the balance of the gun feels "wrong" in my hands. If it feels good to you, then by all means, enjoy!

If you want to shoot "true" .357 Magnum level loads, you need a gun suitable for that. I don't know of any medium or small frame guns that are.
 
I thought ammo manufacutres used 4" vented barrels unless other wise noted. Where did 10" vented barrels come from?
 
Actual Chrono Results from Various Guns & Loads

Here are some actual results from several years ago.

Beartooth 185gr LFNGC (yes 185gr not 158gr)
New WW Cases
Fed 200 Mag
14.7gr Lil'Gun
1.595 OAL
Chron 4 Paces fr Muzzle
Temp 75 Deg

Marlin 18" ------------- 1,713 fps ---------- 1,206 FPE
Ruger BH 6.5" --------- 1,388 fps ------------ 792 FPE
Ruger SP101 3+" ----- 1,161 fps ------------ 554 FPE
S&W M60 3" ---------- 1,175 fps
S&W M360 Ti 1 7/8" -- 1,023 fps ------------ 430 FPE
S&W M340 Ti 1 7/8" -- 1,007 fps

65 Deg F, 5 Paces fr Muzzle
15.0gr A2400, 158gr Horn XTP
FA97 5 ½”---------------1,398 FPS ----------- 690 FPE
SW M66-8 4 1/4"-------1,293 FPS ----------- 587 FPE

16.6gr A2400, 125gr Win JHP
SW M66-8 4 1/4"-------1,462 FPS ----------- 593 FPE


Ref - Original S&W .357 Mag Ballistics

S&W 8 3/8" ------------ 1,510 FPS ----------- 800 FPE…..8 3/8" Bbl


FWIW,

Paul
 
Paul105 great info. The velocity difference between actual firearms is amazing. About ten years ago I purchased a brand new 6' S&W 686 and it wouldn't group better than six inches at 25yds off a rest. Turns out the cylinder gap was large, but within S&W specs so they wouldn't fix it. I'm sure that gun wouldn't have very good velocity compared to other six inch guns with tighter cylinder gaps.
 
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