Loading 38 +p loads in 357 brass

[LUCKYDAWG13]

I want to load up some loads for my daughters 357 what I want to do is use 357 brass and use 38 special +p data My question is
will I still get +p velocity or will it drop down to 38 special What I want to do is make practice ammo
that will match my daughters carry ammo also would like to use Unique powder for this
what do you think

 

[Dudedog]

Will drop a little bit due to the larger case. Usually takes me about .1 or .2gr more to match .38 special vels going to a .357 case.
Of Course it depends on the powder and bullet.

 

[buck460XVR]

what do you think

I think Dudedog is correct.

You should be able to match the velocity of your daughter's carry ammo(as long as you know it) using .357 brass quite easily. Just go thru manuals until you find a recipe that matches. So much .357 info out there it would hard to believe you couldn't find anything, even if you had to go to cowboy type loads.

 

[LUCKYDAWG13]

ok then thank you both

 

[murf]

why don't you try starting at the bottom of the 357 magnum load data. the bottom is probably your desired +p load.

luck,

murf

 

[LUCKYDAWG13]

I wanted to start off lower then magnum first for her and trying to keep the noise level as low as I can

 

[CoalTrain49]

Good news. I have some old Alliant data, probably 2004, that lists the load that you're looking for.

357 mag
158 gr lswc.
Fed 200 primer
6.8 gr Unique
1295 fps
34000 psi

Alliant always lists their loads as max. Start with a 10% reduced load and work up.

I do the same thing with a different powder. Real pleasant load.

If you want the entire document I can send it to you via email. It's .pdf and I don't know how to do it any other way. I can't copy it and turn it into a jpeg.

 

[ArchAngelCD]

You should load the max charge for the .38 Special +P in the .357 Magnum brass and you will still be in the +P velocity range. Then play with the load up or down slightly for the best accuracy. That method has been successful for me.

 

[CoalTrain49]

You should load the max charge for the .38 Special +P in the .357 Magnum brass and you will still be in the +P velocity range. Then play with the load up or down slightly for the best accuracy. That method has been successful for me.

That doesn't seem to be the case here. I'm looking at both loads (357 and 38 plus) using Unique and there's way too much difference to use a rule of thumb method.

357 max is 6.8 gr using Unique.
38 plus max is 4.5 gr using Unique.

It probably has something to do with the case capacity.

My guess is a 38 plus P load of Unique isn't going to get you anywhere close to plus P velocity in a 357 case. Start off with 6 gr of Unique in a 357 case with 158 bullet and see where you are.

I'm using 5.0 grs of a faster powder in a 357 case for plus p velocity.

I'm not trying to be a wise ass here and I apologize if it comes off that way. I'm looking at Alliant load data that most people don't have access to.

 

[PO2Hammer]

With 357 brass I use starting data and work down until I get the desired level.

 

[CoalTrain49]

Here's what I'm using to get to a starting load. Sorry, that's as good as it gets.

 

[LUCKYDAWG13]

Good news. I have some old Alliant data, probably 2004, that lists the load that you're looking for.

357 mag
158 gr lswc.
Fed 200 primer
6.8 gr Unique
1295 fps
34000 psi

Alliant always lists their loads as max. Start with a 10% reduced load and work up.

I do the same thing with a different powder. Real pleasant load.

If you want the entire document I can send it to you via email. It's .pdf and I don't know how to do it any other way. I can't copy it and turn it into a jpeg.

thanks but the 1295 fps is a little more then I'm looking for the data I'm looking at is (+p) 158gr JHP 38 spl 5.2 gr of Unique 761 fps
so I'm going to start at that and work up to 6 6.5 max for her also going to try some 125gr JHP for her first with 6.5 gr of Unique

 

[ArchAngelCD]

That doesn't seem to be the case here. I'm looking at both loads (357 and 38 plus) using Unique and there's way too much difference to use a rule of thumb method.

357 max is 6.8 gr using Unique.
38 plus max is 4.5 gr using Unique.

It probably has something to do with the case capacity.

My guess is a 38 plus P load of Unique isn't going to get you anywhere close to plus P velocity in a 357 case. Start off with 6 gr of Unique in a 357 case with 158 bullet and see where you are.

I'm using 5.0 grs of a faster powder in a 357 case for plus p velocity.

I'm not trying to be a wise ass here and I apologize if it comes off that way. I'm looking at Alliant load data that most people don't have access to.

I'm not sure you understand what the OP is asking for. What does the magnum max charges of any powder have to do with +P pressutes/velocities?

Adding to the velocity spread, on the Alliant site they use a 10" barrel with the . 357 Magnum ammo and only a 6" barrel with the . 38 Special +P.

I have done this and while it's true you don't generate the highest +P velocities you do get close. They you make adjustments for accuracy like I said above. Looking at data doesn't make up for doing your own tests.

 

[CoalTrain49]

I'm not sure you understand what the OP is asking for. What does the magnum max charges of any powder have to do with +P pressutes/velocities?

Adding to the velocity spread, on the Alliant site they use a 10" barrel with the . 357 Magnum ammo and only a 6" barrel with the . 38 Special +P.

I have done this and while it's true you don't generate the highest +P velocities you do get close. They you make adjustments for accuracy like I said above. Looking at data doesn't make up for doing your own tests.

You did that with Unique?

I didn't say not to test your loads. I've been testing 357 loads for a long time. I've worked up loads for rats using bird shot, loads for snubby revolvers, loads for 6" revolvers and loads for carbines using different types of powder. I'll always start with published loads if I can. In this case Alliant has published data (2004) to do just exactly what the OP said he wanted to do. Plus P velocity in a 357 case using Unique.

If you look at the current load data from Alliants website you will see that their max 38 plus P load is 5.2 grs unique/158 lswc/919fps/6" barrel. 919 fps isn't a normal plus P load, 1000 fps is. That tells me that Unique isn't a great powder for 38 plus P loads. It will however work for plus P velocity (1000 fps) in 357 if you put enough powder in the case. 5.2 grs of Unique won't get you there in a 357 case. It won't even get you there in a 38 case. Not surprising as it's always been marketed as a versatile shotgun powder due to it's slower burn rate.

If you don't believe me load up 5.2 gr of Unique in a 357 case and test it as you prescribe.

 

[WrongHanded]

I think if you find min/max data using Unique with the same bullet in both .357 and .38spl, there will be a gap. The max charge for .38spl should be lower than the min (or "starting") charge for .357. So if you're using .357 brass and therefore a .357 revolver, just find a round number between the max .38spl charge and the min .357, and load it up.

 

[CoalTrain49]

I think if you find min/max data using Unique with the same bullet in both .357 and .38spl, there will be a gap. The max charge for .38spl should be lower than the min (or "starting") charge for .357. So if you're using .357 brass and therefore a .357 revolver, just find a round number between the max .38spl charge and the min .357, and load it up.

Exactly. That would be 6.0 grs as I suggested and Alliant load data would verify that.

 

[tightgroup tiger]

Coal train, I think what the OP is asking for is 38+P velocities but he wants to use a .357Mag cases to load those low velocities in.
He doesn't want .357 Mag +p velocities, there is no such thing as that anyways.

 

[Rule3]

Why is this so confusing? No you will not get the same pressure or velocity using a longer case (38 spl vs 357 mag) how could you?

Perhaps just load 38+P in 38 special brass to shoot out or your 357??

If you want to use 357 brass, simply increase the 38+P load data by 10% in a 357 Mag brass.

No it is not directly linear but it is close enough to make up for the 10% increase in the brass difference

 

[LUCKYDAWG13]

Why is this so confusing? No you will not get the same pressure or velocity using a longer case (38 spl vs 357 mag) how could you?

Perhaps just load 38+P in 38 special brass to shoot out or your 357??

If you want to use 357 brass, simply increase the 38+P load data by 10% in a 357 Mag brass.

No it is not directly linear but it is close enough to make up for the 10% increase in the brass difference

I would like to thank you for your help and your suggestions

 

[CoalTrain49]

Coal train, I think what the OP is asking for is 38+P velocities but he wants to use a .357Mag cases to load those low velocities in.
He doesn't want .357 Mag +p velocities, there is no such thing as that anyways.

If there's no such thing why would he be asking about it?

I'm pretty sure I understand what he wanted.

 

[CoalTrain49]

Why is this so confusing? No you will not get the same pressure or velocity using a longer case (38 spl vs 357 mag) how could you?

Perhaps just load 38+P in 38 special brass to shoot out or your 357??

If you want to use 357 brass, simply increase the 38+P load data by 10% in a 357 Mag brass.

No it is not directly linear but it is close enough to make up for the 10% increase in the brass difference

Not sure. Maybe we have some new reloaders here. I certainly hope that's the (357) case.

 

[ArchAngelCD]

@CoalTrain49 you are confusing this whole simple question.

The OP is merely asking how to load a .38 Special +P round in .357 Magnum case, that's all.

 

[Walkalong]

I download .357 cases all the time, and agree with Dudedog who stated you could use .38 Special +P data and add .1 or .2 Grs of powder depending on the speed and get close to +P results in .357 brass. Tweak a hair as needed.

 

[CoalTrain49]

@CoalTrain49 you are confusing this whole simple question.
There are none so blind as those who will not see.

The OP is merely asking how to load a .38 Special +P round in .357 Magnum case, that's all.

I got that.

I told him how to do that back in post #9 and both Rule3 and WH agreed with the number I came up with +/- and they both did it using a different method.

I even provided load data and I said drop the max load of 6.8 grs by 10% which would be 6.0 grains.

Not sure what more anyone can say about it.

OAO.

 

[PapaG]

357 operates at much higher pressure than 38 +P. A high end 38 load will be way below the 357. +p 38 might go 1000 fps and be around 18000. Low end 357 would be 1200 fps at a corresponding higher pressure.
To do what you want, you'll just have to use 38 +p data in 38 cases.