357 Mag. Data Point

[Headhog]

Finally managed to get to the range today with some 357 Mag. loads I put together in the beginning of January. The weather wasn't too bad but the sun kept playing games with the chrono. The temp. was right around 40 F and there was a good wind blowing. The loads I was testing were as follows:

Caliber: 357 Mag (mixed head stamp brass)
Bullet: Missouri Bullets 158 gr. RNFP Hi-Tech coated
Powder: Hodgdon Universal 6.0 gr., 6.2 gr. and 6.2 gr with non-magnum primer
Primer(s): CCI 550 Magnum primer and Federal 100 small pistol primer
COL: 1.585"

When I was putting these loads together I decided last minute to create some of the 6.2 gr. Universal loads with a non-magnum primer just to see how it impacted the results. For the chrono I fired 5 shots and recorded the data for each load. For my rifles I use both my Henry BBS and my Rossi R92. The only reason I test loads in both rifles is that I get about 20-40 fps more velocity from the Rossi.

Here is the chrono numbers:

6.0 gr. Universal from Henry BBS
Avg. Vel.: 1224.0 fps High Vel 1258.2 fps Low Vel. 1200.1 fps SD: 22.9 ES: 58.1 fps

6.2 gr. Universal From Henry BBS
Avg. Vel. 1261.0 fps High Vel. 1280.4 fps Low Vel. 1220.6 fps SD: 24.8 ES: 59.8 fps

6.2 gr Universal Non-Magnum Primer from Henry BBS
Avg. Vel. 1211.2 fps High Vel. 1221.9 fps Low Vel. 1204.0 fps SD: 7.4 ES: 17.9 fps

Results from the Rossi R92 were as expected, the approximate same deviation and spread but with about 2% higher velocities. So no senses providing details here.

What I found most interesting in this test was the results from the non-magnum primer load. Although this load produced 50 fps less velocity, the standard deviation and extreme spread improved greatly. I would like to have retested these results, but unfortunately I only put together 10 rounds of this loads. Just enough to chrono. once in each rifle.

I also fired the magnum primer loads at a 40 yard target. The 6.2 gr load produced a 2 inch 5 shot group. So for me this seems to be the sweet spot in both my rifles.

Going forward I plan to make more of the 6.2 gr. of Universal with non-magnum primers. When the weather improves I will redo the chrono test of this load and also test it for accuracy.

Paul

[fortyshooter]

Looks like Universal is sensitive to primer type. I made some test with standard and magnum primers using Unique and Red Dot and saw little difference in speeds. Interesting results you got.

[Headhog]

Looks like Universal is sensitive to primer type. I made some test with standard and magnum primers using Unique and Red Dot and saw little difference in speeds. Interesting results you got.

Yep that is my feeling also. Thats one reason I want to rechrono the load with the non-magnum primers.

Paul

[Rifletom]

I may try some of those 6.2gr Universal/158's. My 6.0/158's worked very well per my desert shoot. Hey, I'm up to working with new loads. And I'm really liking these Universal loads. A lot!