Seeking real chronograph results for H110 357 mag loads

[Skinnedknuckles]

Actual data over my Shooting Chrony with my guns at about 10' from the muzzle. Use this loading data at your own risk.

15.0 gr H110 under Xtreme 158gr PHP yielded 1235 fps and high max spread in a 4" Taurus M66 and 1720 fps and high max spread in a Rossi M92 with 20". I think I should have had a little higher load to reduce max spread. I lost interest in working with that bullet in magnum loads because so many better 158 gr HP bullets are available so I didn't do more load development.

13.1 gr H110 under an MBC 180 gr coated WFN lead bullet yielded 1140 fps and a tight max spread in the Taurus and 1570 fps in the Rossi again with good spread. Incidentally, these numbers were almost identical to the HSM 180 gr GCWFN factory load, which is what I was hoping for. That stays loaded in the Taurus because we have plenty of bears for neighbors.

 

[Walkalong]

If that was the dominant factor it would take a larger charge to generate a given chamber pressure. But it takes a smaller charge, by approximately 10%.

Sure about that?

 

[ray15]

Sure about that?

Heh, that's odd. First you say it takes less charge because there's less friction, but when I point out that doesn't jive with the data you imply it doesn't take less charge. All examples are 9mm, but the lower charge weights for lead at a given pressure are nearly universal, certainly the rule rather than the exception. And in two of these examples, a ~10% lighter charge makes even more pressure with lead.





.

 

[Hooda Thunkit]

Take a closer look at that data. In all 3 examples, the higher pressure coincides with shorter COL.

Lead or jacketed isn't the only reason to change charge weights.

 

[ray15]

Actually, in one the longer COL has the higher pressure, and another they're essentially equal. And the other? It's HP vs RN, so we should expect the OAL to differ.

I don't have access to data that reads exactly the same in all parameters except the bullet material, as that material choice affects the other factors. But it's no secret that lead generally reaches max pressure at lower charge weights, often by 10%.

 

[Walkalong]

But it's no secret that lead generally reaches max pressure at lower charge weights, often by 10%.

I would have to have someone prove that to me. It takes less powder to get lead out of a barrel than plated or jacketed due to friction.

I'd love to see the tests with pressure and velocities shown.

 

[ray15]

I'd love to see the tests with pressure and velocities shown.

It would appear ignoring the data I've assembled for you as well as the trend it illustrates is your choice. There's plenty of data out there if you are really interested. The above results were the first three examples I found on Hodgdon's site. A quick perusal through a Lee manual or any book with a significant amount of load data makes the trend clear.

 

[Steve in PA]

I shoot plenty of plated Rainier bullets out of my .357's. All are 158 loaded over 15.0 grains of H110. No load data, but the shoot great with no issues.

 

[Walkalong]

It would appear ignoring the data I've assembled for you as well as the trend it illustrates is your choice.

Well, I sense I have upset you, so I will accept your explanation and leave it alone.

 

[ray15]

Hello all, just a request for information here since I don’t own a chronograph. I’m just curious what kind of velocities we get in the real world when loading 357 mag with H110, especially in 158gr bullet weight.

I currently load 16gr powder with a Rainer plated 158gr bullet and magnum primer which is right in the middle of Hodgdon published data. Shooting from a 4” Security Six. I’m not trying to create anything super hot, just trying to ballpark the velocities I’m currently getting.

Had a chance to chrono today, and ran some W296 (same as H110) loads with the xtreme 158HP plated bullet though my 4" GP100.

Xtreme 158gr. plated HP .357"
16.4gr. W296
CCI Magnum SPP, Starline brass
OAL - 1.555"
Average: 1209.8 FPS
SD: 24.3 FPS
Min: 1183 FPS
Max: 1237 FPS
Spread: 54 FPS

Xtreme 158gr. plated HP .357"
15.7gr. W296
CCI Magnum SPP, Starline brass
OAL - 1.555"
Average: 1150.8 FPS
SD: 32.6 FPS
Min: 1099 FPS
Max: 1181 FPS
Spread: 82 FPS

I ran some Hornady XTP HPs at the same charges to check the correspondence against the Hodgdon factory data, which uses the XTP. Speeds were essentially identical to the above with .357" plated bullets. It appears safe to go up to the book max of 16.7gr of H110/W296 with a plated bullet in place of the XTP if you duplicate their seating depth. I may try it to see if the SD declines any more. It's likely my fault it isn't better at 16.4gr; this is my first run of .357 mag and I'll get better at it.

 

[Walkalong]

I ran some Hornady XTP HPs at the same charges to check the correspondence against the Hodgdon factory data, which uses the XTP. Speeds were essentially identical to the above with .357" plated bullets.

I have had the same experience with 158 Gr XTPs and X-Treme 158 Gr SWCs in.38 Spl. loads. Shot pretty much the same as each other.

 

[ray15]

I have had the same experience with 158 Gr XTPs and X-Treme 158 Gr SWCs in.38 Spl. loads. Shot pretty much the same as each other.

Yeah, there was almost no difference. Since Hodgdon's velocity numbers are in a 10" barrel I wanted to establish the speeds their XTP loads would achieve in my 4" revolver. So I bought some 125 and 158 XTPs to use as reference bullets. They are actually about the cheapest jacketed hollowpoint in .357 if you only want 100.

You quoted an error in my post - they are of course .357" plated bullets I was using. 9mm on the brain.

 

[Walkalong]

You quoted an error in my post -

Corrected.