Going from .38spl to .357 Mag

ScotchMan · December 6, 2011, 08:10 AM

Hi all,
I currently load .38spl and would like to start loading .357 Magnum as well. What do I need to make this transition?

-Can I use the same dies?
-Can I use the same bullets?
-Are the cases sized differently so if I use the same dies they will need to be adjusted?
-Can I use the same primers?

I have heard of people loading .357 Magnum loads in .38 cases because that's what they have. While I think thats a bad practice, it makes me think the parts will be interchangeable.

DeeDubya · December 6, 2011, 08:40 AM

Same dies

Maybe the same bullets (lead bullets that shoot well in lower 38spl velocities might cause leading in the 357)

You shouldn't need to adjust the resize die but of course the seating/crimping die for the longer case

357 mag will use small pistol magnum primers

Never attempt to load 38spl with 357 recipes. Pressures will be higher because of less case capacity. Also, it would probably blow up a 38spl revolver, even one rated for +P loads.

This is exactly why I would never shoot someone elses reloads nor will I give my reloads to someone else. It's just not worth the risk.

spacecoast · December 6, 2011, 09:05 AM

Quote:

357 mag will use small pistol magnum primers

Not necessarily, it depends on the load. I only use magnum primers for top-end loads using H110. Mid-range and mild .357 target loads are fine with standard primers. The powder manufacturer's web site should have details on which primers they recommend/have tested.

Quote:

Never attempt to load 38spl with 357 recipes

Agreed, this could be disastrous if the rounds were accidentally used in a relatively weak .38 special chamber. Even in a .357 chamber, the peak pressures would be higher and potentially dangerous.

David Bachelder · December 6, 2011, 09:09 AM

I'm not familiar with any die sets other than RCBS. The RCBS38/357 die set comes with washers (spacers). The washers are used to switch from 38 to 357 without having to reset the die adjustments. This saves a great deal of time. More time reloading and less time adjusting dies.

overkill0084 · December 6, 2011, 09:58 AM

-Can I use the same dies? Yes. The same dies will work w/ .38 special, 357 Mag & .357 Max.
-Can I use the same bullets? In most cases, yes. However, bullet choice must be appropriate fior the velocities they will be used at. Swaged lead bullets would very likely turn out poorly with full steam loads. Plated can work, but you need to pay attention to the velocities they will be used at. Beyond 1200 fps, things can get spotty.
-Are the cases sized differently so if I use the same dies they will need to be adjusted? Sizing, not a problem. Belling the mouth, bullet seating and crimping will require adjustment. It's not that bad. IIRC, the case length difference is actually fairly small.
-Can I use the same primers? Yes, for a lot of loads. Slow burning ball powders will likely require mag primers. Many other powders don't seem to care. Check your data and see what the loads your looking at were developed with.
I have heard of people loading .357 Magnum loads in .38 cases because that's what they have. While I think thats a bad practice, it makes me think the parts will be interchangeable. I also think it's bad practice. I don't load anything in a .38 case that I wouldn't shoot in an alloy snubbie. But that's me. There are ways to make it work, but that's another, more advanced thread. Hint: Hunt down the writings of Elmer Keith.
You can always load .357 down to .38ish levels once you get a handle on things and some experience. Once you settle in, you will find .357 a very pleasant & versatile cartridge to work with.

ScotchMan · December 7, 2011, 12:22 PM

Thanks for the tips guys. I despise the process of adjusting seating dies with empty cases and then pulling the bullets from the failed attempts. I use a seperate turret for every caliber I load so I don't have to worry about the settings. I *may* get a second set of .38/.357 dies if it turns out to need different settings and I think I will load enough to justify the cost.

I'm using Power Pistol which is pretty fast burning, so I think I will try small primers if my research deems it safe.

Thanks again for the advice.

Poodleshooter · December 7, 2011, 02:09 PM

Quote:

I despise the process of adjusting seating dies with empty cases and then pulling the bullets from the failed attempts.

I just back the seater out nearly all the way every time, then screw it in and seat incrementally until depth is set to where I want it. I crimp separately.
It's rare that I have to pull a bullet using that method.

TXGunNut · December 7, 2011, 02:35 PM

I treat .38 and .357 as different cartridges...because they are. The .38 Special is based on a blackpowder cartridge and is very accurate and pleasant to shoot in all but the smallest and lightest of revolvers. The .357 Magnum is a relatively modern high velocity, high performance revolver cartridge generally using jacketed bullets and larger, stronger cases. In most cases different powders are used and the slowest powders may require magnum primers. You won't get optimal performance from either cartridge by using components (other than primers) that work well in the other. Yes, they are the same caliber and use the same dies and are sometimes fired in the same firearms but you won't be able to get the most from either unless you treat them as individual cartridges.

zippy13 · December 7, 2011, 02:47 PM

I treat .38 and .357 as different cartridges... because they are.

Amen!
It's just a convenient coincidence that you can use the same dies.

spacecoast · December 7, 2011, 03:16 PM

Quote:

You won't get optimal performance from either cartridge by using components (other than primers) that work well in the other

Not sure what you mean by "optimal", but there are guys here who would swear that their .38 special wadcutter loads shoot more accurately from their .357s if loaded into .357 brass, not to mention keeping the cylinder chambers cleaner. I don't shoot well enough one-handed to notice a difference.

BigJimP · December 7, 2011, 04:38 PM

I have a separate set of dies / on a separate toolhead for .38 spl and .357 mag ...for convenience.

I load the same bullet for both ...158gr jacketed bullet...

I use small pistol primers for both loads ...

I use the same powder for both loads ....Hodgdon Universal ...the amount of powder is different for .38 spl vs .357 mag ..

and they're very accurate / good rounds...

I shoot way more of the .357 mag personally ...probably 10,000 rds a yr or so in a variety of revolvers because I really like the caliber - and I really enjoy shooting revolvers along with my semi-autos / but I keep 15 boxes of .38 spl around too ...for young shooters in the family.

mrawesome22 · December 7, 2011, 05:11 PM

Sounds like you need some reloading manuals.

December 6, 2011, 08:10 AM	#1
ScotchMan Senior Member Join Date: July 3, 2011 Posts: 1,368	Going from .38spl to .357 Mag Hi all, I currently load .38spl and would like to start loading .357 Magnum as well. What do I need to make this transition? -Can I use the same dies? -Can I use the same bullets? -Are the cases sized differently so if I use the same dies they will need to be adjusted? -Can I use the same primers? I have heard of people loading .357 Magnum loads in .38 cases because that's what they have. While I think thats a bad practice, it makes me think the parts will be interchangeable. __________________ Everyday Loadout NRA Instructor NRA Member

December 6, 2011, 08:40 AM	#2
DeeDubya Senior Member Join Date: November 1, 2011 Location: San Marcos, TX Posts: 114	Same dies Maybe the same bullets (lead bullets that shoot well in lower 38spl velocities might cause leading in the 357) You shouldn't need to adjust the resize die but of course the seating/crimping die for the longer case 357 mag will use small pistol magnum primers Never attempt to load 38spl with 357 recipes. Pressures will be higher because of less case capacity. Also, it would probably blow up a 38spl revolver, even one rated for +P loads. This is exactly why I would never shoot someone elses reloads nor will I give my reloads to someone else. It's just not worth the risk. __________________ DW NRA Life Member

December 6, 2011, 09:58 AM	#5
overkill0084 Senior Member Join Date: August 7, 2010 Location: Northern, UT Posts: 1,162	-Can I use the same dies? Yes. The same dies will work w/ .38 special, 357 Mag & .357 Max. -Can I use the same bullets? In most cases, yes. However, bullet choice must be appropriate fior the velocities they will be used at. Swaged lead bullets would very likely turn out poorly with full steam loads. Plated can work, but you need to pay attention to the velocities they will be used at. Beyond 1200 fps, things can get spotty. -Are the cases sized differently so if I use the same dies they will need to be adjusted? Sizing, not a problem. Belling the mouth, bullet seating and crimping will require adjustment. It's not that bad. IIRC, the case length difference is actually fairly small. -Can I use the same primers? Yes, for a lot of loads. Slow burning ball powders will likely require mag primers. Many other powders don't seem to care. Check your data and see what the loads your looking at were developed with. I have heard of people loading .357 Magnum loads in .38 cases because that's what they have. While I think thats a bad practice, it makes me think the parts will be interchangeable. I also think it's bad practice. I don't load anything in a .38 case that I wouldn't shoot in an alloy snubbie. But that's me. There are ways to make it work, but that's another, more advanced thread. Hint: Hunt down the writings of Elmer Keith. You can always load .357 down to .38ish levels once you get a handle on things and some experience. Once you settle in, you will find .357 a very pleasant & versatile cartridge to work with. __________________ Cheers, Greg “At the core of liberalism is the spoiled child – miserable, as all spoiled children are, unsatisfied, demanding, ill-disciplined, despotic and useless. Liberalism is a philosophy of sniveling brats.” — P.J. O’Rourke

December 7, 2011, 12:22 PM	#6
ScotchMan Senior Member Join Date: July 3, 2011 Posts: 1,368	Thanks for the tips guys. I despise the process of adjusting seating dies with empty cases and then pulling the bullets from the failed attempts. I use a seperate turret for every caliber I load so I don't have to worry about the settings. I may get a second set of .38/.357 dies if it turns out to need different settings and I think I will load enough to justify the cost. I'm using Power Pistol which is pretty fast burning, so I think I will try small primers if my research deems it safe. Thanks again for the advice. __________________ Everyday Loadout NRA Instructor NRA Member

December 7, 2011, 02:35 PM	#8
TXGunNut Senior Member Join Date: January 16, 2010 Location: If you have to ask... Posts: 2,860	I treat .38 and .357 as different cartridges...because they are. The .38 Special is based on a blackpowder cartridge and is very accurate and pleasant to shoot in all but the smallest and lightest of revolvers. The .357 Magnum is a relatively modern high velocity, high performance revolver cartridge generally using jacketed bullets and larger, stronger cases. In most cases different powders are used and the slowest powders may require magnum primers. You won't get optimal performance from either cartridge by using components (other than primers) that work well in the other. Yes, they are the same caliber and use the same dies and are sometimes fired in the same firearms but you won't be able to get the most from either unless you treat them as individual cartridges. __________________ Life Member NRA, TSRA Smokeless powder is a passing fad! -Steve Garbe I hate rude behavior in a man. I won't tolerate it. -Woodrow F. Call Lonesome Dove My favorite recipes start out with a handful of used wheelweights.

December 6, 2011, 09:09 AM	#4
David Bachelder Senior Member Join Date: August 23, 2011 Location: Trinity, Texas Posts: 636	I'm not familiar with any die sets other than RCBS. The RCBS38/357 die set comes with washers (spacers). The washers are used to switch from 38 to 357 without having to reset the die adjustments. This saves a great deal of time. More time reloading and less time adjusting dies.

December 7, 2011, 02:47 PM	#9
zippy13 Senior Member Join Date: August 23, 2008 Location: SoCal Posts: 6,442	I treat .38 and .357 as different cartridges... because they are. Amen! It's just a convenient coincidence that you can use the same dies.

December 7, 2011, 04:38 PM	#11
BigJimP Senior Member Join Date: February 23, 2005 Posts: 13,195	I have a separate set of dies / on a separate toolhead for .38 spl and .357 mag ...for convenience. I load the same bullet for both ...158gr jacketed bullet... I use small pistol primers for both loads ... I use the same powder for both loads ....Hodgdon Universal ...the amount of powder is different for .38 spl vs .357 mag .. and they're very accurate / good rounds... I shoot way more of the .357 mag personally ...probably 10,000 rds a yr or so in a variety of revolvers because I really like the caliber - and I really enjoy shooting revolvers along with my semi-autos / but I keep 15 boxes of .38 spl around too ...for young shooters in the family.

December 7, 2011, 05:11 PM	#12
mrawesome22 Senior Member Join Date: November 9, 2005 Location: Ohio, Appalachia's foothills. Posts: 3,779	Sounds like you need some reloading manuals.