Hand loading 357 mag

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NeilMo

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Hi to all. Wondering if I could get some clarification. I'm some what confused. Using Hodgdon H110 for the 357 mag with 125 grain JHP, I have 4 different load date manuals that call for a wide range of powder weight. Lyman at 21-22, Nosler 14.9-15.9, Speer 18-20 and Hodgdon's web sight states 21-22 grains.
Do you see my confusion?
And just for comparison, Hodgdon says the 44 mag calls for 23-24 grains of H110.
I am currently using Titegroup, and seems to work well. Just thought it odd there's that much differences between manuals.
I would like to see your feedback.
Thank you Neil.
 
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NeilMo said:
Hi to all. Wondering if I could get some clarification. I'm some what confused. Using Hodgdon H110 for the 357 mag with 125 grain JHP, I have 4 different load date manuals that call for a wide range of powder weight. Lyman at 21-22, Nosler 14.9-15.9, Speer 18-20 and Hodgdon's web sight states 21-22 grains.
Do you see my confusion?
And just for comparison, Hodgdon says the 44 mag calls for 23-24 grains of H110.
I am currently using Titegroup, and seems to work well. Just thought it odd there's that much differences between manuals.
I would like to see your feedback.
Thank you Neil.
Click to expand...

Go with the lowest weight load and work up to satisfy your particular needs as recoil and accuracy will vary. You'll know the best load when you shoot it. I would lean toward the data from the bullet companies like Speer, Hornady and Nosler. I think they test a lot more with specific bullets than the powder companies. Personally I use the Hornady manual and cross reference with Speer who seem to be on the upper side of the equation.

Stay away from hot 357 loads with 125 gr. bullets. They will flame cut your revolver. Just a heads up.;)
 
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The biggest anomaly you cite, the Nosler data, is easy to explain. 14.9 to 15.9 is what they quote for a 158 gr. bullet, not a 125. The Speer data is for their bullet, in their test firearm.
 
Pisgah, You are right. Just looked it up and it is a 158gr bullet. My bad! And thank you for the input.
 
Thank you for the reply. Very helpful. And yes I always stay away from top ended loads.
 
I will advise that with H-110/W-296 that loads should not be less than 10% below maximum. This is due to the potential of this powder to not ignite in a uniform manner when lightly loaded. H-110/W-296 is best when seeking the highest velocity possible from the magnum pistol calibers.
 
Every manual publisher uses different guns, different components, different bullet weights, and different seating depths to generate their data. Find the range that most closely matches your desired configuration (especially with H110) and go with that range. This is why it is valuable to have multiple up to date manuals.
 
You will see different load data for the reasons cited by Amanwearingahat in post #7 . That's due to all the many variables.
Get at least 4 different references . Try to use data for your exact bullet, not just the same weight ...Hornady bullet use Hornady data.
Cross check those numbers with powder manufacturer .
When in doubt , start with lowest starting charge and work up slowly .
Ask questions but always double check info gleaned from the internet, easy to hit the wrong key while typing and Published Data Rules ...buy loading manuals .
Gary
 
When faced with so much conflicting data, use either the powder manufacturers data or the projectile manufacturers data as your starting point to work up from.

Anytime you alter the recipe, back off some and rework if you are loading at MAX

Back in the late early eighties I worked up my H110/Winchester 125 JHP load. 21.7 grains lit up by a CCI 550 primer

Now about 40 years later, I still use the 21.7 grains of H110 but have switched to a Winchester magnum SP primer. I reworked the load, and it could have gone a bit higher, but I was used to 21.7 grains

During a projectile shortage a couple of decades ago, I also reworked the load with an IMI 125 JSP and 21.7 grains was still in the performance envelope

IMI%20125%20JSP%20As2.jpg

In more recent years, I stockpiled projectiles. I am down to almost 5,000 of the IMIs and I am not sure of the Winchester count

If there is anything I learned from my recent move, it is that I need to post a WTS ad and start reducing the tonnage in the loading room
 
Groo here
Look at the amount of bullet in the case when crimped...
Makers very the size and depth of the hollow point ,angle and shape of the
nose, size of the flat, and flat or concave the base
All this changes the depth the bullet seats in the case to meet the over all length and there for how much space there is for the powder.
Changing the load....
 
Here's a pic of all the different 125gn bullets from the Midway 357 load map. Too many variations in lengths and cannelure positions to start guessing. As others have said already, the seating depth is quite different from brand to brand. Example- Nosler seats about .025" deeper in the case than a Hornady XTP and is the reason the powder charge is considerably lighter.
I'd suggest downloading the entire Midway 357 load map. It has load data for every bullet in the below picture and several more from 110gn all the way up to 200gn. I found it much easier to use specifics when I started loading 357 Magnum, and much safer to get an exact starting load.
 

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Published data has been pressure tested & with the EXACT set of components listed . If one chooses to change even one it's prudent to go with a starting load & work up slowly in your gun . As stated above different bullets even of the same weight have different seating depths . More of available space in a case = less pressure , a deeper seated bullet decreases this which raises pressure . Primers will also have an effect on pressures . Look at data for the weight bullet you want to use . Find the powders that give highest velocities with the least amount of pressure & best case fill . These will be the best suited for THIS particular load . When people chase speed with light for caliber bullets add a slower ball powder is when you have flame cutting & / or forcing cone wear . The 125 JHP 357 loads excel at varmit eradication be they 2 or 4 legged . For other uses you'll be better served with more appropriate bullet weights . Reloading is like following a recipe when cooking . If one insists on improvising sometimes it don't turn out so good .
 
If in doubt, use the lowest listed powder charge. If I'm using Hodgdon powder, I'll use Hodgdon data. If I'm using Hornady bullets I'll use Hornady data.

As mentioned above, most testing facilities will have their own lot of components (brass, powder, bullets and primers) which may be different from an other lab's supplies, even though the "same" components are used. Some labs test with universal receivers and some with actual guns. Some lab's testing equipment (barrels, receivers, and/or guns) may be well worn and some may be brand new. If I saw two test data that were exactly the same, I would question the source of that data...
 
All manuals are diff because all testing is diff. Diff test platforms, components, climates, temps, it all matters. It is why reloading data is a guide & not a bible. When working with something new, I look for 3 vetted data sources & average the middle & max data. I rarely if ever use starting data for anything unless looking for a really minor load.
 
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I just spent 2 hours over on that Midway 357 load map. index - powered by h5ai v0.29.0 (https://larsjung.de/h5ai/)

Done in 1999 and lots of good consolidated data. I have a few problems with it. The recipes for H4227 are different than I4227. We are told every day they are exactly the same.

Also they use a concept of RGS for groups size which is actually only for the MAX load they show. None of the other lesser powder amounts are shown. I almost never see the MAX load with the best group size, so what does it even mean? Whose bad MAX is the best?

Anybody else follow that link for 357 data?

Prescut
 
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Just went out today with some 125gr 357 mag reloads for testing in my Old Model 6" Black Hawk. Started at 21.0 gr of 296, zero signs of pressure. Brass just fell out. Didn't group worth a dam. 8.5gr of Unique did way better
 
Just an FYI. I've actually loaded 21 grains of H110 behind a 125 grain Hornady XTP. Wanted to see if I could get better than 1450 fps from my 4 inch model 620.

First, this was as loud or louder than a 500 Magnum. Also had a muzzle flash that extended halfway down a 50 foot range according to a couple of witnesses.

Second, posts about flame cutting are 100% true. While it didn't do any real harm prior to this excursion the hottest 357 Magnum I had run in my 620 were American Eagle SJSP range Magnums. So I sort of broke the virginity on my top strap with this beast of a load and to this day feel a bit guilty about it.

Final note, out of a 20 inch 1892 this load will hit over 2200 FPS and the bullet will not spin apart into pieces. However with a steel crescent butt plate it is a bit brutal to to shoot. If I ever re-stock that 1892 it's going to get a shotgun style stock.
 
oddshooter said:
I just spent 2 hours over on that Midway 357 load map. index - powered by h5ai v0.29.0 ([url]https://larsjung.de/h5ai/)[/url]

Done in 1999 and lots of good consolidated data. I have a few problems with it. The recipes for H4227 are different than I4227. We are told every day they are exactly the same.

Anybody else follow that link for 357 data?

Prescut
Click to expand...

Prescut, back around the era this was published, IMR4227 and H4227 were still 2 different powders from 2 different manufacturers. They were very close in burn rate, but not the exact same powder. If I am remembering correctly, one was manufactured in Australia and the other in Canada. But when Hodgdon bought out IMR, they dropped one of them and dropped the H4227 name and just started selling IMR4227 powder. I see what you mean on the Midway data, but I attribute this to the fact that the powders are similar but different.
 
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