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Hi - I’m about to load some 357 magnum rounds for my new Rossi R92 16” 357. I normally use 2400 for 357, but I ran out and will use W296.
The Hodgdon site shows a range of 15.0 to 16.7 grains of W296 for a 158 gr HDY XTP bullet — however I’m using cast 158 gr powder coated boolits, and not sure how that affects the load data.
I’m thinking that 15.8 grains of W296 would be a good starting point. I’m priming with CCI 550 Magnum primers.
Any thoughts/suggestions?
Thanks
out of a rifle it may be a little fast for even a PC Cast Boolit. Pistol Data says probably 1500fps with that charge (158 xtp Data).
rifle will be 2-300 fps faster usually. It Really Depends on the Hardness, how good the coating is, if it will work well or not in my experience.
296 is same as H110, and is a great magnum load. I have used extensively for 44mag, you will like. Just make sure you are with min-max. It's a flashy powder.Quote:
Originally Posted by ghh3rd
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PC is a little bit of a game changer. IME, you can get away with a softer alloy. At that speed you may or may not need gas checks.
This is the original Win data 14.5 grs - 296- 158 gr lead.
. https://www.thehighroad.org/index.ph...gnum.2913/full
H-110 (Hodgdon labeling of W296) is my preferred powder for .357 magnum. I gas check 158’s cast with Lyman No2 and conventional lube so I’m not a lot of help with advice on powder coating other than advising a heavy roll crimp in the crimp groove. The only other thing I might share is the data I worked off of was in Lyman’s 4th edition.
For rifle data it shows a 158 grain Lyman #358665 cast with Lyman No2 in a 20” barrel:
Starting load: 14.4gr. Velocity: 1708
Max load: 15.9gr. Velocity: 1857
Attachment 322787
Based on that data and my alloy I started at 15 grains and worked up. I have no idea of your alloy or how powder coating will impact pressure in comparison to this data set. Your rifle will tell you what it likes. My carbine is different than yours. I have also found some notable lot to lot difference in H-110. The load that shot best in my carbine with an old 8 lb jug I have since shot up was 15.6 grains. I will add that my cast is sized .003 over grooves to shoot through a micro groove barrel. With a new lot of powder recently opened, 15.3 grains closely duplicates the old lot of powder both in velocity and accuracy. Good luck with your load work up with W296. It works well for me in multiple .357 magnums.
Willie
Edit to add: Lead bullets generate more pressure than jacketed bullets with the same powder charge. Use lead specific data to load cast bullets.
Lead or coated lead always down loads a bit. I would go with the starting jacketed data & work it up.
I too have found H110/W296 to be great with .357 and 44mag. No help to the OP but my 24" Rossi 92 with tang peep sight and aperture front target sight will routinely produce 2" groups at 100 yards. 15.3gr pushing 185gr WFN GC'd store bought Cast Performance boolits. Always a good sign all is working well when your ammo produces a nice blue lube flower on the muzzle.
I suggest finding a similar lead bullet to the one you're using that has data. With comparable weight and the same amount of bullet in the case, you would have a much better starting point.
Fred, that's interesting. I've always found my coated loads perform nearly identically to normally lubed bullets. No need for jacket data. I've even read here or there suggestions that the loads with PC'd bullets are lower pressured and at a higher velocity....it was suspected the slickness of the PC helps the bullet glide down the barrel easier...Quote:
Originally Posted by fredj338