Want to use less powder than minimum on my .357 mag

[allain]

I have a new Ruger Blackhawk .38 Special/.357 Magnum revolver (about 200 rounds.)

I want to shoot .38 Special loads in .357 brass? Would there be a problem here?

For example: with a 158 gr. LSWC, using Bullseye powder, the minimum loading for a .38 special is 3.0 grs. and for the .357 Magnum it's 4.9 grs.

The .357 mag brass is 0.135 inches longer than a .38 special, but other than that, I can’t see that would be a dangerous under load for the .357.

I know that with rifle loadings, a load under the “suggested minimum” may detonate, but I don’t know if this applies for the .357.

What do you think about this?

 

[tightgroup tiger]

With Bullseye there may be a problem going below .38spl minimum loads. I don't think I would do that.

Some of the older recipes in the loading manuals have a warning about Bullseye and minimum loads in that you have to make sure the bullet clears the barrel. Lyman's 45 edition has this warning and that's for 38spl cases.
Using .357mag cases will add more air space and exasperate the problem.

A lot of this depends on the barrel length of your pistol.

Be careful.

I know that with rifle loadings, a load under the “suggested minimum” may detonate, but I don’t know if this applies for the .357.

I don't think it's possible to detenate a .357mag with low pressure, but
you need to worry more about sticking a bullet in the barrel and not knowing it when you fire the next one.

 

[Blue68f100]

I've done it but bumped the charge up by 0.1-0.2gr to compensate for the larger case. As long as you confirm the bullet makes it out of the barrel your good. But you will find that the accuracy is very poor if going to slow the reason for the bump in charge.

 

[moxie]

Best to get a good manual and follow the data exactly.

Fooling around with tenths here and tenths there outside the limits of the manual is asking for trouble. You say you "can't see that would be a dangerous under load for the .357." What are you basing that on? Years of experience as a reloader? How many? Formal training as a ballistician? Don't take chances with stuff that goes bang. Follow the book!

 

[maxxhavoc]

It should be fine if you stick to powders that work in both. Don't get the idea to try it with H110/W296.

 

[Lost Sheep]

Thanks for asking our advice

I have a new Ruger Blackhawk .38 Special/.357 Magnum revolver (about 200 rounds.)

I want to shoot .38 Special loads in .357 brass? Would there be a problem here?

For example: with a 158 gr. LSWC, using Bullseye powder, the minimum loading for a .38 special is 3.0 grs. and for the .357 Magnum it's 4.9 grs.

The .357 mag brass is 0.135 inches longer than a .38 special, but other than that, I can’t see that would be a dangerous under load for the .357.

I know that with rifle loadings, a load under the “suggested minimum” may detonate, but I don’t know if this applies for the .357.

What do you think about this?

The detonation thing has nothing to do with rifle cartridges vs pistol cartridges. It has everything to do with large volume cases and slow powders.

All smokeless powders burn rather slowly at normal pressures (that is, one atmosphere, or 14.7 psi). These powders burn considerably faster when pressures go up into the thousands of psi. These powders have a performance "envelope" at which the burn behaves in a predictable, stable and consistent manner. If you try to run a powder at lower than its optimal pressure, you can get odd behaviors, like detonation, pressure spikes, bullets that stick partway down the barrel while the burn continues and pressure builds up again (effectively against a barrel obstruction). Not everyone believes in detonation, but there is no argument that light charges of slow powders, especially in voluminous cases is an iffy proposition, best avoided.

Fast powders are more forgiving of lighter-than-minimum loads. The main danger there is if you load so light that you have a bullet that does not leave the barrel. That sets you up for an obstructed barrel and all the disaster that goes with that.

But think about this: If you take a .357 Magnum cartridge and set the bullet deep enough that the overall length is 38 special length, you effectively have a 38 special in your chamber and can use the same load data a 38 special uses.

Or, you could increase the 38 special load data proportional to the increase of the interior volume of the case (under the bullet) and get similar performance as if you loaded 38 special brass. I do this all the time.

Lost Sheep

 

[transtech]

As Lost Sheep says, perfectly fine to use 38 Special loads in 357 magnum with a tweak to make up for case volume difference, that is the beauty of the versatility of the 357 magnum. It is my belief that the difference is approximately 10% so I increase charges accordingly.

 

[243winxb]

powder position problem? http://www.thehighroad.org/showthread.php?t=607180

 

[Dudedog]

I never loaded min .38 special loads in .357 but I have loaded a bunch of what would be middle of the road/max .38 loads in .357 with no problems yet.

Still have my fingers and eyes, brains gone but that's another matter.

 

[Average Joe]

Just use the load data for .357 minimum charge, work from there.

 

[rsrocket1]

3.5g Bullseye would work fine with a 158g bullet in a .357. I've gone down to 3.0g but it's pretty smokey/sooty with some flakes and sparks that fly out in all directions. 3.0g Red Dot is a much cleaner burning low recoil load, but Bullseye would work fine.

Everyone should "work down'' loads at least once to see what a stuck bullet feels like. You as a reloader should know that you are expecting it and you'll instantly tell that there is a bang, slight flame and smoke and virtually no recoil. If the bullet makes it fully into the barrel, just open the cylinder and knock the bullet back with a brass rod. A primer only squib might not leave the cylinder so you simply knock the bullet back into the case.

Just like learning how to put on chains at home on a nice day, you want to know what to expect and how to deal with a stuck bullet on your terms. You don't want to learn how to do it for the first time on a packed firing line or with chains on a busy highway at night in a blizzard.

No you won't have a detonation or position problem with 3g Bullseye in a 357 magnum case.

 

[greyling22]

I have not used bullseye, but I have done that with other powders. you are PROBABLY fine, but guarantees. Maybe split the difference and go with 4 grns?

If you get the pressure too low you run the risk of the bullet not sealing properly and getting poor accuracy.

 

[cfullgraf]

Many load manuals will have minimum 357 Mag loads higher than the maximum 38 Special loads even with the same powder. But if it is fine to shoot light 38 Special loads in a 357 Magnum, then equivalent loads in 357 Magnum cases should be possible.

Because the 357 Magnum case is larger, it will need a little more powder than the 38 Special load to account for the slightly greater internal volume of the 357 Magnum case. When I got started in reloading 35 years ago, I remember comments in the various publications to this effect

i agree with Blue68f100, Lost Sheep and transtechi.

If you have a chronograph, you can use it to work the 357 Magnum case load down to 38 Special performance. Be sure to load and shoot some of the 38 Special loads in your revolver to calibrate it. I'd stop on the safe side and have the 357 Magnum case load a bit faster than the target 38 Special load.

While bullets stuck in the barrel are not the end of the world, they are a pain in the ass and can be disastrous if not caught before the next cartridge is fired.

This is not appropriate with powders that are load sensitive such as W296/H110.

 

[rcmodel]

Powder 'detonation' in light handgun loads is an unprovable old wives tail.

More like what happened in every case was a double charge, two bullets seated in the case, or a bullet stuck in the bore already from too light a charge.

rc

 

[joneb]

I have had good results with Bullseye and 158gr cast bullets in .357 mag cases using standard primers. I worked a good load for a 357 mag short barrel starting at 3.8gr of Be.

 

[Toprudder]

Are you married to Bullseye for what you want? If what you are looking for is light recoil with a 357 casing, I suggest trying a different powder. If you can find Trailboss, it would be great for this. You pretty much fill up the casing leaving enough room to seat the bullet. A very fluffy powder, it fills up the casing with a very light charge, so you will not have a problem with position sensitivity.

Other powders I've tried in 357mag or 38spl that has worked well have been 700x, BE-86 and Titegroup.

 

[vongh]

I have used and have currently on hand a lot of 158 grain cast lead wheel weight round nose using 6.5grains of IMR 800x its not full power but it definitely wont get a bullet stuck. Comfortable to shoot many rounds and very accurate (in my gun). I have used 4.5grains of Bullseye with the above bullet and it is also a good plinking round.

 

[Rule3]

Just use the load data for .357 minimum charge, work from there.

I would use this also. In a Redhawk it will feel like a mild 38 special.

Don't make it more complicated than it needs to be.

Alliants max for a 158 gr Speer LSWC is 4.8 so 10% less is 4.3 grains of BE which is just a bit over a a Max 38 +p per Alliant data (3.9 gr)

http://www.alliantpowder.com/products/powder/bullseye.aspx

 

[WestKentucky]

I went pioneering with 357 loads a while back laddering down to a crazy low charge where the bullets started travelling so slow you could watch them go down range. Accuracy was dismal, and I called the tests complete at that point for fear of a squib by continuing. The trend was declining accuracy, declining reliability, declining consistency, and we were well below the recoil of a 22 mag. The only good thing that came of that test was that it gave me a use for 500 9mm bullets I wasn't planning to use...my 9mm dies are ordered now and I need to buy bullets. One round that worked particularly well was a very soft lead 9mm bullet 124gr at .357 diameter shooting about 750fps. No mentionable recoil, very accurate, very quiet, but that was really odd as nothing around it was worth mentioning. The key to doing this with any safety at all is to look at "cowboy loads" as they typically use the best powders for low pressure shooting.

 

[ljnowell]

Any published 38 special load is going to be safe in a 357 case. I have yet to see one that wouldn't be. Yes there is more case capacity but I have chronographed light loads in both cases, there isn't as much difference as you would think.

 

[gamestalker]

My recommendation would be to work the load down, it's much safer doing it that way, by maintaining the rule of thumb regarding load development. So rather than working up from minimum, you'll simply be working down from minimum, and your focus will be directed at any and all possible issues.

It will help to reduce component waste, and save you the hassle of having to pull a bunch of bullets. You could maybe load 6 or so at each charge increment, of say .1 gr,. and work down.

GS

 

[rcmodel]

Why not just load 3.5 and 4.0 test loads and be done with it.

3.5 was the standard factory .38 load for 75 years.
(826 FPS)
So probably 750-775 FPS in a longer .357 case.

So 4.0 in a .357 case can't be too far off from standard .38 Spl.
(About the same or a little faster velocity.)

Rc

 

[Nite Ryder]

Most Cowboy Action shooters have been using light 38 special loads in their 357 magnums for years. However, it would be my guess that most of these guys reload 38 special cases instead of 357 magnum cases. I've loaded thousands of rounds of 38 special loads into 38 special cases using either 90 grain bullets or 125 grain bullets, and 3 to 3.5 grains of Clays powder. You just need to make sure the bullet comes out the end of the barrel before you shoot another round. We had one shooter that stacked 5 lead bullets in the barrel of his Ruger Blackhawk, one right behind the other one. It didn't cause any visible damage to his gun, but it damaged his ego.

 

[Kosh75287]

I just think I'd try it with almost ANY other powder than Bullseye (and H110).

 

[Catpop]

I like Lost Sheep's answer about seating the bullet deeper in a 357 case. That way you eliminate the 38 residue ring, the extra case volume problem and can load to 38 spc specs. Just make sure you don't seat the bullet too low and raise the pressure.
Catpop