38spl loaded to 357mag....possible???

pmgnicol

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Hi there. I have a S&W686-6 with a 6inch barrel and currently shoot 158gn rn projectiles and 5.5gns of AP70 powder. This is good enough for me to meet minor power factor for IPSC comps. What I want to know is...is it possible to load 38spl cases to 357mag loads. Having checked the ADi website for 357mag cases I would need 6.3gns of AP70 to meet power factor for major. The 38spl cases still have loads of room in them to accommodate 6.3gns. Its less than a grain higher than what I am shooting now and I am seeing no adverse effects on the cases, primers etc at present. It would be amazing to be able to up my powder charge in 38spl to major power factor. Any thoughts........
 
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It is possible.

It is not the greatest idea in the world. For one thing, there's always the chance then, of forgetting and dropping a Magnum'd .38 Spl into a .38 revolver. For another, your ammo might get mixed up. For a third, somebody else might come to get a hold of a box of your Magnum'd .38 loads, and use them in a .38 revolver.

For all of the potential Bad Things That Can Happen, buying some used .357 Magnum brass, or a bag of 500 brand-new cases from Starline is cheap insurance.

As a side note, I would also suggest taking velocities from reloading data with a grain of salt. It may be less, it may be more. A chronograph can be had pretty cheaply.
 
Ditto for what Wise A said.

Especially that bit about not believing what you see in reloading data. For example Vihtavouri uses a "6.5 inch" barrel for their 38 special data but it must be the fastest 6.5 inch barrel on the planet because what I've seen across my chronograph with my 6 inch Dan Wesson 15-2 is over 150 fps under what Vihtavouri's data would indicate.
 
Skeeter Skelton was doing what you ask about years ago. He wrote several articals on his 357 mag loads, in 38 spl brass, using 2400 powder. An internet search should turn up what you are looking for.
 
Wise_A's advise about says it. My Wife has a J frame and a LCR. She knows 38spl fits her revolvers. She doesn't know what all the numbers are that I've written on the ammo boxes.
357mag cases new or once fired, will be cheap insurance. If nothing else also you'll avoid the carbon build up before the cylinder throat.
 
Thomasinaz's suggestion is good
Do a search....read about it


From searches, the Forum knowledge base results list several particulars
Only using new 38 special cases
357 cases availability
Seating long
Crimping in different locators on the bullet
And many more....

My thought
Keep it simple
Use 357 cases in 357 guns and 357 load data
38 special cases in 38 special guns and 38 special load data

I shoot a 686 6 inch and buying 1000 new Starline 357 cases makes reloading life so simple. So many issues just disappear!
 
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There have been previous threads about this, and indeed it is possible, except bullets should be seated out a bit to enlarge the available case volume under the bullet. The principal reason that .357 cases are made longer is so that they cannot be fully chambered in a weaker .38 Special revolver.
 
Yes ago I did not have hardly any 357 mag cases and was too poor to buy any . I loaded up 38 spl cases using older load data to approx 357 mag levels . I did notice it shortened case life but I had so many 38 spl cases it really didn't matter . They were shot out of my model 19 .
 
Anything is "possible" Is it advisable or safe is another question.

Yes you can load 38 special to NEAR 357 mag levels but due to the 38 spl being a bit shorter you need to allow for that. So at LEAST a 10% reduction in 357 powder charges would be wise.

Brian Pearce has a spiel about it in some magazine

Also depends a lot on what powder(s) you use.

Trying to "read" handgun brass for "signs of over pressure" is really like tea leaves.
The probable only sign over over pressure will be a major Kboom,:eek:

I have never used AP70 (n) but per ADI it is kinda/sorta around the same speed as Unique and Universal within 5%
For whatever that's worth.
 
Even though I'm the only one to use my reloads, I'm a bit uneasy loading 38 up to 357 or even +P levels. I have 3, 38 Special revolvers but only one 357 Magnum and I wouldn't want to run a "hot+" round through my snubs.

One thing to remember is that with the decreased case capacity the pressures in a 38 Special case, using the same charge as used in a 357 Magnum case, will be much higher...
 
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I load, and shoot 38/44, never have had a problem. All ammo boxes are marked as to the load, and guns for use.

Also keep in mind that S&W proofs their handguns to MUCH higher pressure than SAAMI, IIRC somewhere around 50K. When the 38/44 was a factory round it was advertised that Colts could handle them. The Colt Official Police was built on a .41 caliber frame. Not only did they advertise them for the OP, they also advertised the small Police Positive safe for use of the 38/44.

As I have pointed out before I was friends with a detective who carried factory 38/44 in his duty J frame. Not sure how much he shot it with the hot loads but I do know of one occasion, his gun did not blow up. Nor did it show any indication of becoming out of time from one round.

Even standard ammo puts wear on a gun, though it could take a century before that wear is noticed. The hotter the ammo the quicker the wear, minimal use of hot ammo is doubtful to blow a gun up. Unless something is wrong with the gun in the first place.

38/44 tends to give impressive results with less pressure than .357, could be that less powder is needed for the same velocity. IIRC the pressure for 38/44 was around 25K CUP, far below than .357 standard pressure. I doubt I am the only one to clock random factory ammo at much higher velocity than possible for a correct load. Or much less, though so far I have not had a factory squib, but some damn weak ones. I weigh every single charge on 38/44 loads, well all loads.

If a person is shooting from a gun rated for 35K, then 25K is not going to be dangerous. Reloads should never passed to anybody in any load unless the source is well known. Use common sense, and make wise decisions. Remember that we are not responsible for your decisions, no matter how much free advice we give.
 
I only go as far as maximum recommended 38spl loads out of my 357 guns.. my 38spl guns get turned down 38spl loads.

But as noted above, I don't want to confuse the issue.
 
Seems to me I loaded 38 special nickel to 38/44 data and fired in 357 revolver. Maybe cross check this for your self. I think this is 357 lite.
 
I think there's a misconception that all 357 magnums revolvers are stronger than 38spl revolvers. The main difference in 38sp,l and 357 mag is case length. The extra case length reduces pressure. While you can cram the same amount of powder in a spl case there isn't any room left over or not enough room to dampen the pressure spike that would occur when it is fired. Take the very strong GP 100 for example. Both 38spl and 357 mag versions of this gun are virtually the same with exception of the cylinder length. While these guns have the same metallurgy and are the same dimensionally ( except for the length of the chambers) , Ruger will tell you never to load anything past +P power levels.. This is all because of the lack of leftover space within the 38spl case after you load a magnum charge of H110 or W296 into it. Short answer is yes, it can be done, but how many times before you run out of luck and hurt yourself?
 
The cylinder length on the GP100 is the same between 38spl, and 357. The only difference is the reaming of the chambers. Ruger heat treats all their guns to the same specs. I would guess that S&W does so also, it just doesn't make sense to have two separate processes for the same frame. Companies are not going to spend more money to make a weaker frame.

The problem with the K frame is the undercut forcing cone. If a 1930's Colt Police Positive can handle 25k CUP I would bet the modern K frame can in limited use.
 
"Also keep in mind that S&W proofs their handguns to MUCH higher pressure than SAAMI, IIRC somewhere around 50K. When the 38/44 was a factory round it was advertised that Colts could handle them. The Colt Official Police was built on a .41 caliber frame. Not only did they advertise them for the OP, they also advertised the small Police Positive safe for use of the 38/44."

It even goes beyond that. Back in the 1930s the ammunition manufacturers advertised that .38/44 ammunition could be used in any sound .38 Special revolver, warning only that the recoil would be heavier if used in lighter framed revolvers. Many, many people back then, especially cops, used .38/44 ammunition in whatever .38 revolvers they had. I don't remember reading anything about Ka-Booms resulting from that practice, but it probably did accelerate wear.
 
If you are truly sure that you and you alone would be using this over pressure ammo this might be an OK idea.
If there is a possibility not probability but a possibility that anyone other than you may use this ammo I don't see it as a good idea.
I am pretty careful about my loads but I wouldn't trust myself to be positive of what every individual .38 bullet pressure is whenever I pick one up.
Brass is cheap enough insurance that no one will drop one into an older .38 J frame. A much safer option to me.
40 years ago one of my less than diligent friends blew up a brand new Chief's Special with a high pressure .38. It was in an indoor range and the top strap was never found. He was lucky it didn't get buried in his forehead.
 
The ".357 load in a .38 casing" Skelton used did not use just any bullet. It was a cast SWC with TWO crimping grooves. Seat and crimp the bullet in the lower groove and the resulting, longer cartridge had about the same powder space as a .357 casing with the same bullet. Seat and crimp the bullet in the upper groove and the resulting shorter cartridge had about the same powder space as a .38 Special.

That particular bullet was designed that way because, back then, .357 brass was new, scarce and expensive while .38 Special was like white on rice.

People forget or never knew; Skelton and the others weren't doing this with just ANY bullet.
 
Yes, you can probably load 38spl to 357 levels, but you could also load it to grenade levels too, why? Buy a gun in caliber that performs at the level you seek, not try to make something it isn't.
 

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