.38 loads in .357 brass?

chaparrito

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Waiting for the arrival of my Security Six. I've never loaded .38 or .357 but am wondering this: I do what amounts to a midrange 44spl load in magnum brass. It's a sweetheart and I can shoot my 629 all day. Can I do a similar thing - a .38 charge in .357 brass, so I don't have to fiddle with different cases?
 
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I would be careful.... Check to make sure that your load is at least at the starting level for .357. Too little powder could result in a bullet stuck in the barrel. I wouldn't advise going below the minimum .357 loads if you are using .357 brass.
 
No problem in duplicating any .38 Special ballistics in a .357 case, but it won't be the same powder charge, usually a little greater. I do it sometimes. You don't have to adjust the sizing die, but you will have to adjust the expansion plug and the seating die. There are rings available that go under the die locking nut to use dies set for .38 Special with the .357 case. Sometimes the rings come with new die sets.
 
Use the minimum or start load of 357 Mag in 357 brass.

The loads were developed for the particular brass and as imakmst just wrote best to use the specific loads.

If you want light 357 loads look for the lowest velocity and pressure of published loads

Start loads of some powders in 357 Mag are pretty mild

Depends on what powders you have,
 
I do what amounts to a midrange 44spl load in magnum brass. It's a sweetheart and I can shoot my 629 all day. Can I do a similar thing - a .38 charge in .357 brass, so I don't have to fiddle with different cases?

The same common sense you used when doing this in 44 would apply to 38. Presumably you don't have a rigid adherence to only what is published in books since you do this in 44 already.
 
The Lyman cast bullet handbook gives a lot of lower-velocity recipes for the .357. Most of the starting loads given have slightly higher MVs than .38 Special and use slower powders. My experience has mainly been in the use of Unique powder with 148 grain DEWC bullets, and I have duplicated factory .38 Special load performance with no problems. The advantage is that you get a slightly shorter bullet jump to the forcing cone using the .357 case vs the .38 Special with the bullet seated at the case mouth.
 
There are MANY 38 special loads that will shoot excellent groups
in a 357 Magnum, be they lead, jacket or the newer coated bullets.
Some don't like the "Build up" the shorter case leaves in the
cylinder that supports the longer 357 case but with the correct
cleaning units, this is removed in quick order and good as new.

Most shooters shoot 70% or more 38's in the magnum for their
training sessions but the full loads are also fun to shoot.

Enjoy the new arrival.
 
I would be careful.... Check to make sure that your load is at least at the starting level for .357. Too little powder could result in a bullet stuck in the barrel. I wouldn't advise going below the minimum .357 loads if you are using .357 brass.
I started reloading .357 Magnums with .38 Special loads in about 1978. I have never had a problem as described in the above quote. I have even used Bullseye/wadcutter loads in a 4" .357 (3.2 gr. Bullseye) and all bullets reached the target at 50' and quite accurately too...
 
I have found that 148 grain full wadcutter bullet loads using 4 grains of Unique in both .38 Special and .357 Magnum cases differ very little in MV and grouping performance in the same gun. That may not be true for every revolver.
 
As for that "Ring"..................

just go to the hardware store and look at the washers for the 1-11/8 " bolts with the thickness that you need.

Being an Ironworker, I had no problem finding one that worked. :D

edit 4/29 (post 20 )
This construction washer is thinner than the store bought, I guess?
store .165"......... this washer used in "Red Iron" is only .141" thick.
 
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I have shot 38 loads in 357 brass for years without any problems.
Some off my favorite plinking loads are 38 +++++p or 357 ----p, that grey area between the two. I have never used 38 start data when I do this mid 38 and up. 231/HP38 under a 158 lswc in the Grey area is one of my favorites.
 
As for that "Ring"..................

just go to the hardware store and look at the washers for the 1-11/8 " bolts with the thickness that you need.

Being an Ironworker, I had no problem finding one that worked. :D

The problem with that approach is that SAE specifications for 7/8", 1", and 1-1/8" washers include a 0.165" standard thickness. My RCBS rings actually measure 0.129" thick (although theoretically they should be 0.135" thick). I suppose one could somehow work down the thickness of a 0.165" thick washer, but it would take some time and effort to do so.
 
There is NO difference.....

There is no difference between .38 and .357 brass except for that teenitesy extra length to keep from putting .357 rounds into a .38 revolver. It serves no other purpose. I start my shooting rounds with .38 and switch to magnums later in the session. By using .357 brass for all of them I don't have to clean the crud rings out of my cylinder at the range.

IF you think that extra bit of volume is going to make a difference, add 1/10 of a grain to your .38 loads.
 
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"IF you think that extra bit of volume is going to make a difference, add 1/10 of a grain to your .38 loads."

As I said earlier, I did some testing some years ago using 4 grains of Unique with DEWC bullets in both .357 and .38 Spl cases, couldn't see much difference in MVs or grouping using my nice ca. 1960 Colt .357 Magnum.
 
Same here....

"IF you think that extra bit of volume is going to make a difference, add 1/10 of a grain to your .38 loads."

As I said earlier, I did some testing some years ago using 4 grains of Unique with DEWC bullets in both .357 and .38 Spl cases, couldn't see much difference in MVs or grouping using my nice ca. 1960 Colt .357 Magnum.

I've come to the same conclusion, just giving whoever worries about this a 'correction' factor so they can feel better.:D:D:D
 
For the sake of logistical simplicity, I've never loaded .38 in .38 SPL brass. I really can't think of a reason to do it since I don't own any guns that only chamber .38 SPL.

Edit:
Probably should mention I'm pushing 158's around 1000fps...so maybe call it .38 +P
 
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I started reloading .357 Magnums with .38 Special loads in about 1978. I have never had a problem as described in the above quote. I have even used Bullseye/wadcutter loads in a 4" .357 (3.2 gr. Bullseye) and all bullets reached the target at 50' and quite accurately too...

Risky. Light-load rupture is a possibility. Small amounts of fast powder in large cases can lead to flash over, where the powder is settled in the case below the primer hole. Upon ignition, the primer flash goes over the powder, instead of through it. Unpredictable results can occur. You may never have a problem. mikld reports he has never had a problem. Your gun may blow up.

I wouldn't do it, especially with fast powders.
 
Risky. Light-load rupture is a possibility. Small amounts of fast powder in large cases can lead to flash over, where the powder is settled in the case below the primer hole. Upon ignition, the primer flash goes over the powder, instead of through it. Unpredictable results can occur. You may never have a problem. mikld reports he has never had a problem. Your gun may blow up.

I wouldn't do it, especially with fast powders.

In all my years I have never heard of anything even close to your story about flash over and blowing up a gun. And frankly, it sounds like something someone made up as a joke. Can you provide any verification of this ever happening?
 
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I have used 11.5gr of 2400 in .357 cases with a 158gr LSWC or LRN bullet. MV around 840fps. Never any problem.
Jim
 
Just doesn't happen....

Risky. Light-load rupture is a possibility. Small amounts of fast powder in large cases can lead to flash over, where the powder is settled in the case below the primer hole. Upon ignition, the primer flash goes over the powder, instead of through it. Unpredictable results can occur. You may never have a problem. mikld reports he has never had a problem. Your gun may blow up.

I wouldn't do it, especially with fast powders.

No one has ever been able to duplicate a light load causing an explosion. IF the load is so light that a bullet sticks in the barrel, the next shot will cause a problem, most likely damaging the gun. A low charge may cause erratic ignition and inconsistent results, but not an explosion. That's the official stance.

It is conjectured that what people consider to be explosions from light charges of fast powder, are that they are actually double charges of fast burning powder which WILL blow up a gun.

The unofficial stance is that, for my own purposes and using a snub for minimal barrel friction, I've experimented with low charges and have never in 30+ years had a failure to fire, a hang fire or an explosion.
 
I use 357 cases for all my loads. Mostly, in the plus P range, or somewhat above. My revolvers tend to be on the small size, and I don't do much full powdered loading.
I read on this forum that increasing 38 SPL loads by 15% will give the same velocity as using 38 SPL cases. I have found that to be a good starting point. I can make adjustments from there. I like that I can work anywhere from light target to full MGN in the same cases. One of the advantages of hand loading.
I do make sure that there is 357 MGN data for the same bullet and powder, and that I am within the data. Some powders might not be suitable for "scaling up". At least, it is safe to assume that . An example might be a very fast powder that might get into a non linear range by adding 15%.

Best,
Rick
 
If you want specific .38 spl level load data for the .357 mag look at the "cowboy action" data. You will find they are .38 spl loads for the .357 mag case.
 
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