Trying to complete .357 Magnum testing.

[Brick]

On the range today even though conditions were marginal at best. This time testing was conducted using my .357 Magnum Winchester 1892 carbine.
All powder charges were dispensed by powder measure and brought to final weight trickling powder in to balance scale. Scale was check weighted within 0.5 grs of charge weight. e.g. for charge weight 18.8 grs check weights totaling 19 grs. were used to confirm scale accuracy.

As always your comments are invited. I also did some testing with Blue Dot. Those results and explanation and critique will be posted soon.

[Hoppy]

Thanks or the update. I'm encouraged. The JHP 296 load is almost 1300 Ft/lbs, that's nice. I'm hoping to put together a 158 grain 296 load at that kind of energy. My Marlin is 18.5" barrel I believe.

[Hoppy]

I have finally gotten some reloads to the range.

I recently put a scope on my marlin 1894 357. I know, some won't like it but my eyes can't see like they used to.
Last week I did a little sighting in of the scope. Didn't have enough ammo to truly dial it in but it was close. This week I was testing different charges so I left the scope as is. I started at 14.5 grains of 296 which is max for 158 grain lead on the hodgdon website. I'm shooting Lee tumble lube 158 grain semi wad cutter. They have been powder coated.

The first shot was about 3" of bullseye at 100 yards and about 1720fps. I can't remember exactly and my app didn't record it. It started recording after that first shot. I shot 5 14.5 grain rounds, then skipped to 14.7, 14.9, 15.1, 15.3.
Max velocity was 1796 with 15.3gr. It seemed like only the first few were accurate though. After that I was missing paper on some shots.

I thought maybe I was leading the barrel or my scope came loose but after getting home I don't think so. I cleaned the gun the barrel was dirty but not leaded. Scope seems right and still boresights well.

I'm going to have to load up more and hit the range again. I'll probably load up 10 of the 14.5 and just shoot for accuracy and then maybe try increasing beyond the 15.3. I saw no signs of pressure. I've read about people loading 16 grains for this bullet. Not sure if I'll get accuracy.

I'm any event, I know I can load 14.5 get approx 1700fps and some accuracy that I can fine tune. That should work for my allegheny county late season deer gun.

Brick, in my lyman book, you are above max it looks like, how was accuracy? I would like to see 1800fps with my load and good accuracy at 100yds

[Brick]

Checking back on my Sierra Edition 5 for .357 Magnum Rifle it shows H110 at 19.2 grs. as max for the Sierra 140 gr JHP I was shooting Win 296 for the same bullet is 19.5 grs. max. My preferred loads came out as W296 19.1 grs with an avg velocity of 2033 fps and H110 18.8 grs. giving 1951 fps avg velocity. Accuracy with both was acceptable.

[Hoppy]

Thanks brick. What does Sierra edition say for 158 grain swc?

[Brick]

Thanks brick. What does Sierra edition say for 158 grain swc?

Sierra doesn't show loads for cast bullets. Only their own jacketed stuff. Stick within recommended loads from the manufacturer of the powders you're using. The Hodgdon data is very reliable, just bear in mind their testing uses pressure vessels not actual firearms so your chronographed results will almost always be lower than published data shows.

[Hoppy]

Thanks brick. I worked up a box of 15.5 grain 296 with my lee 158 grain swc. These are tumble lube but I powder coated them.

One of my groups from the chronograph..



There wasn't a huge jump in velocity as I finished my last round at 15.3 grains. But seemed fairly good accuracy wise. Sighted my scope and called it good. I think the biggest variable might be my roll crimp.

[Brick]

Looks like a very respectable load. Should serve you very well for whitetail in our eastern forest land. Let us know how well it works on your first deer!

[243winxb]

Old Winchester data from 1996. Needs a mag primer.

[Brick]

^^^^^^ Interesting information....Surprised to see W231 as a choice but, I must ask is this one of those that lists the MAXIMUM load with instructions to reduce by 6% or so and work up incrementally?