reloading .357 Magnum

jhagberg88

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hello all,

a friend gave me some .357 brass to reload so we can shoot it out of one of his guns, is .357 the same bullet head as a .38 Special?
 

RKG

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The nature of your question suggests to me that you should do a bit more research before fooling around with .357 Magnum reloads.

A) The .357 Magnum round is dimensionally identical to the .38 Special round, except that the case is 0.135" longer. This was done to prevent inadvertent chambering of .357 rounds in .38 revolvers.

B) However, the .357 Magnum round operates at far higher peak pressures than does the .38 Special round, which means that a bit more care and caution is required.

C) In particular, if you intend to achieve full-power .357 loads, you're going to have to experiment with powders (e.g., H110, 2400) that can be a bit more demanding than the powders most often used for .38 loads (such as Bullseye and Unique). You'll also have to decide whether use of a magnum primer is necessary, in which case the charge has to be adjusted appropriately. (I use H110 primarily for .357 Magnum loads, both in revolver and carbine, and routinely use CCI magnum primers.)

D) While most revolver loads need something of a decent crimp for ignition purposes, .357 rounds require a comparatively stiff roll crimp, both for ignition purposes and to prevent bullet setback as a result of recoil.

E) Likewise, I stay away from light slugs with full power loads. One reason is that some .357 revolvers have displayed forcing cone cracking issues with full power light slugs. Another is that powders such as H110 are not recommended for light slugs, given their burn characteristics.

E) If you intend to shoot cast slugs, you'll have to decide whether achieving full power .357 velocities is consistent with the alloy your slugs are cast from. I, for one, stay away from cast slugs with full power .357 loads, though others have used them successfully.

Bottom line: get a couple of reloading manuals and study them. You might also get a subscription to Handloader magazine and look up some past articles on loading for .357 Magnum, particularly those authored by Ken Waters.
 
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The .357 Magnum and .38 Special have the same bore diameter and therefore use the same diameter, and generally the same type and weight range, bullets - typically .357" in jacketed, and .358" in lead. Other than that, they are, as RKG indicates, very different beasts and considering that you had to ask your original question it's apparent that you should learn a bit more about handloading before actually doing any. That's not a criticism - after all, we all started from a state of limited knowledge - just good advice.
 
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A concise summary right on the money!
The nature of your question suggests to me that you should do a bit more research before fooling around with .357 Magnum reloads.

A) The .357 Magnum round is dimensionally identical to the .38 Special round, except that the case is 0.135" longer. This was done to prevent inadvertent chambering of .357 rounds in .38 revolvers.

B) However, the .357 Magnum round operates at far higher peak pressures than does the .38 Special round, which means that a bit more care and caution is required.

C) In particular, if you intend to achieve full-power .357 loads, you're going to have to experiment with powders (e.g., H110, 2400) that can be a bit more demanding than the powders most often used for .38 loads (such as Bullseye and Unique). You'll also have to decide whether use of a magnum primer is necessary, in which case the charge has to be adjusted appropriately. (I use H110 primarily for .357 Magnum loads, both in revolver and carbine, and routinely use CCI magnum primers.)

D) While most revolver loads need something of a decent crimp for ignition purposes, .357 rounds require a comparatively stiff roll crimp, both for ignition purposes and to prevent bullet setback as a result of recoil.

E) Likewise, I stay away from light slugs with full power loads. One reason is that some .357 revolvers have displayed forcing cone cracking issues with full power light slugs. Another is that powders such as H110 are not recommended for light slugs, given their burn characteristics.

E) If you intend to shoot cast slugs, you'll have to decide whether achieving full power .357 velocities is consistent with the alloy your slugs are cast from. I, for one, stay away from cast slugs with full power .357 loads, though others have used them successfully.

Bottom line: get a couple of reloading manuals and study them. You might also get a subscription to Handloader magazine and look up some past articles on loading for .357 Magnum, particularly those authored by Ken Waters.
 
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Good advice here. One thing to consider is that you don't necessarily have to load to full power using magnum primers and magnum pistol powder (like 2400 or WW296/H110). I load most of my plinking loads w/ standard primers and WW231 or Unique. My loads are somewhere in the .38+P range.

The big danger here is that you must be very careful not to double charge the case!! 6 grains of pistol power gets lost pretty easily if your not careful.
 
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Hi can I use small rifle primers instead of small mag pistol primers, since that is what you use when you load 454 casull and use H110 and both work on very high pressure.
Dean
 
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Hi can I use small rifle primers instead of small mag pistol primers, since that is what you use when you load 454 casull and use H110 and both work on very high pressure.
Dean

I wouldn't. You'll likely get mis-fires and light strikes. Also a .357 case has less volume than a casull, so I'm not sure what kind of affect it'll have on pressure.

I'm not even 100% sure they'll even seat correctly.
 
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MisterHappy

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Dean.

Not to be jumping on a new member, but... if you are here asking these questions, you really should do some reading, or find a clinic to learn the art and science of reloading.

It's fun and safe if done properly, but if you're not sure what you're doing, it can be unsafe.

If you're trying to invent a new load from interweb info, don't do it.
 

milktree

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Hi can I use small rifle primers instead of small mag pistol primers, since that is what you use when you load 454 casull and use H110 and both work on very high pressure.
Dean

Unlike large rifle and large pistol primers which are have different depths, small rifle and small pistol primers are dimensionally identical and will seat in either interchangeably. But it's still a bad idea. Don't do it. Primers aren't that expensive, just get the right primers.
 
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Hi I have been reloading for a very long time with great success, what I was asking was not a stretch the casull round uses a rifle primer due to the fact that H110 is a very slow powder as far as pistol powder goes, and yes they fit in the primer pocket what I was asking is how much SPARK differance is there between the too primers.
 
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I believe the 454 Casull calls for the use of a rifle primer because it operates at a SAAMI pressure of 50,000 cup, which is similar to the pressure that many rifle cartridges are at and well beyond most pistol cartridges. Rifle primers use thicker metal (which is why many pistols can't set them off) so as to be better able to withstand the higher pressures. I'm not sure of the relative spark difference - I believe the correct technical term is "brisance" - between the two, and it would vary somewhat between brands in any case.
 
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No, you can't.

The pocket depths are different. (small pistol is same diameter as small rifle, but not same height) Each is sized for the specific primer pocket. (diameter and depth)

CLICK HERE FOR ALL PRIMER DIMENSIONS

http://www.thehighroad.org/showpost.php?p=3936874&postcount=28
Small Rifle

Cup Thickness Diameter Height
CCI 400 . .020" .1753" .109"
CCI 450 . .025" .1750" .113"
CCI BR4 .025" .1755" .109"
Federal 200 .019" .1757" .111"
Federal 205M .0225" .1744" .1075"
Remington 6 ½ .020" .1753" .109"
Remington 7 1/2 .025" .1752" .110"
Winchester SR .021" .1750" .109"

Large Rifle
Cup Thickness Diameter Height
CCI 200 .027" .2112" .118"
CCI 250 .027" .2113" .118"
Federal 210 .027" .2120" .117"
Remington 9 1/2 .027" .2100" .119"
Winchester LR .027" .2114" .121"

Brand/type Power Average Range Std. Dev
1 Fed Match GM215M 6.12 5.23-6.8 .351
2 Federal 215 LRM 5.69 5.2-6.5 .4437
3 CCI 250 LRM 5.66 4.5-7.4 .4832
4 Winchester WLRM 5.45 5.1-6.0 .2046
5 Remington 9 1/2 LRM 5.09 3.5-6.75 .6641
6 Winchester WLR 4.8 4.1-6.0 .4300
7 Remington 9 1/2 LR 4.75 3.7-6.25 .5679
8 Fed Match GM210M 4.64 4.0-5.6 .3296
9 Federal 210 LR 4.62 3.7-5.5 .3997
10 CCI BR2 4.37 4.0-5.0 .2460
11 CCI 200 LR 4.28 3.8-4.8 .3218
12 KVB 7 LR Russian 4.27 3.8-4.8 .2213
13 Rem 91/2 (30 yrs old) 4.16 3.8-4.8 .3427
14 Rem LP 4.47 3.2-5.6 .5171
15 KVB 45 LP Russian 3.89 3.3-4.2 .2232
16 CCI 300 LP 3.18 2.7-3.5 .2406
17 Federal 150 LP 3.11 2.6-3.5 .2090
18 Fed Match GM150M 3.05 2.6-3.7 .2299

And here is another chart - only rifle primers ... http://www.jamescalhoon.com/primers_and_pressure.php

Primer cross reference chart:
http://www.handloads.com/misc/primers.asp

http://bulletin.accurateshooter.com/2011/04/primers-and-pressure-analysis-by-james-calhoon/


Your reloading book will tell you specifically what primer to use for what.

Use only what the book says.

454 casull in the book says to use small rifle.
357 mag says to use small pistol.

They are not the same primer pockets.

Thanks I was just trying to see if I could get away with not stocking another primer.
 
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