Advice on reloading .357 Magnum, please.

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RM

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I would like to try reloading .357 magnum, and I'm not sure what powder to use. I have 158g Berry's plated bullets and need to make 165,000 power factor to shoot in IDPA ESR division. The gun I'm using is a SW-66 with 4 inch barrel, and I'd like to minimize recoil to the extent possible. Powders I have on hand: longshot, unique, Power Pistol, W231 (not a good choice, so I have read), and titegroup. Which one or two powders should I try? Thank you.
 
Thanks Vern. Yes, I can pick up some powder at a gun show, if the ones I have aren't good choices.
 
Vern, in this case I disagree.

Using plated bullets with minimizing recoil the goal? 296 and H110 are bad choices here. If I had jacketed bullets and was going for full snort loads, that'd be a different story.

Try the unique in the midlle of the listed charge weights would be my advice.

Also: Having a chrono would be a big help for this task.
 
I have loaded alot of Berrys plated bullets, I was told to load them as if they were cast and not to push them to hard.
So I never tried H110 or W296 behind a plated bullet but I have had great luck with Bullseye.
A can of Bullseye will last you for a while (small charges) it meters good and burns pretty clean BUT I dunno about the power factor.
I love reloading .357 Ive tried so many different powders and bullets and theirs still so many more to try :)
 
I'll vote with Ben--although I don't use Unique. Of the other powders you have, look up load data for Powder Pistol. Needless to say, start at the bottom of the recipe.

If you find the recipes for powder-puff 231 357 loads, those should be considered. Otherwise, I agree, 231 is not an "overall' powder for this cartridge.

And, if you are adventurous, consider reading up on Power Pistol in 38 Special, and consider doing some load development to move the 38Special charges into a 357 case.

Jim H.
 
You need to get at least 1,045 FPS with that bullet to get an IDPA Power Factor of 165,000.

That can be easily reached with plated bullets and medium burn rate powder.

I would try 6.5 grains of Unique, or WW-231. Either one should do nicely.

H110 or 2400 would not be a good choice for this application.

rc
 
I would second the use of Unique. It's been around for awhile but it's still one of the best for medium loads for cast bullets. I would consider any copper washed bullet to be the same as a cast one. You should be able to make a P.F. of 165 with Unique. :)
 
if you have unique on hand i would sure use that first...... i use bullseye to reload .357 magnum and .38 spl because it goes so far.... around 3 grs.BE for .38 spl and around 6 grs. BE for .357 magnum.............. you can get a lot of loads from a pound of bullseye!!

like uncle ted said... the 2nd amendment is my carry permit......................
 
I have used 231 for this exact task and was thoroughly satisfied with it. Unique is as good in every parameter except cleanliness. 231 leaves the gun almost spotless.
 
I have recently starting using Power Pistol it does a great job but I am using mid to high loads not sure how it would work in a lower load. Also H110 and W296 both need Magnun primers.
 
HP-38 / 231 works for me. As suggested in an earlier post, a chrono is the tool to use when working up loads. Also, consider which powder meters best with your reloading equipment.
 
Yup, I agree... H110 or 296 would not be the cans I would reach for on this application. Unique is a better choice. By the way... I have that same side arm and it's been a good buy so far.

LGB
 
I'm relatively new at loading the .357 myself and haven't loaded any plated or jacketed slugs yet.
I have however loaded and shot around 300 Lee mold cast 158gr tumble lubed with Lee lube - over Red Dot at 1000 fps with good accuracy and little fouling - that mostly at the cone and easily removed.
a 'target load' that lets you know it's a .357 you are shooting.
 
I don't know how to figure power factor, and I don't have a chrono for exact velocity, so this might not help.

I like TG for mild magnum loads - I use the "do not exceed" load listed in Lee's manual (double-checked with the manufacturer's website) over my Missouri bullet 158 LSWC and really like it. The manual says it should generate 1100fps. It shoots flat and I can kill clay pidgeons at 50 yards w/out difficulty - so it's an accurate load.

Best of all, the load generates less pressure than other powders, so I don't have the nasty leading that AA#5, Unique and Bulleseye give me.

Q
 
It Really Is Unique

I have a closet full of powder of all sizes, shapes and burning rates, and one of the two I fall back on is 6.5 g Unique under a 158 g LSWC in 357. The other is Bullseye - not necessarily in 357, but in 38, 45 and 9mm for sure. I am always working up loads with others, but when I have to load up a bunch in short order/short notice, there are consistencies in those two that are unsurpassed (no aspersions intended - I use AA2/5, Red Dot/Green Dot, Clays etc etc etc too).
 
utilizing what you have on hand, i'd go with unique. my personal choice, however, would be green dot. i load GD in my .38-44s now, and am ever reminded how mild the recoil is for the velocity delivered (1060 fps).

i turned a friend on to GD and that's what he prefers now in his 6" M28. his load of choice: 6.0gr GD under 160 swc.
 
Of the powders you listed I would use Longshot. I'm fairly sure you can make power with that powder with room to spare. I don't care for Power Pistol because of the excessive flash it produces, flash you really don't need during a competition. If you can get a hold of some HS-6 that would probably be the best choice since that powder will generate less pressure and probably less felt recoil than the other choices.
 
I bought some Solo 1250 at the gun show yesterday. I loaded some midrange .357's with it last night. Plan on trying them out after work today. Looking for 125's at 1300 FPS, give or take a bit.
 
Power Floor 165,000

http://www.ccidpa.org/idpa-pf.html The 158gr needs to be going a minimum of 1045fps by looking at the chart. The Hodgdon website gives loading data for cast lswc, these loadings should be good for a plated bullet. Use one with the Lower Listed Pressure "CUP" HS6 is listed at 15,500 CUP's seems really low, i wonder if its a missprint??:confused: Alliant Unique might work, but looks like a maximun charge is needed. 6.0 gr for lswc, Jacketed needs 7.7 gr. if you go by the Alliant Powder guide.
 
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Power factors in IDPA and IPSC/USPSA competition are not ceilings, they are floors. Your ammo must be a 'combat' or 'self defense' loading. Generally, this is a small velocity/energy range that is capably of producing the maximum projectile action (expansion) in a human sized and structured target. Insufficient velocity/energy and one is penalized or disqualified from competition. Any excess power is a waste and a detriment felt in extra recoil and muzzle flip.

Gun games are 1911 centric and the 1911 platform is used for a wide variety of gun games. Target games like Bullseye use very light loadings of medium to heavy bullets for paper punching accuracy, Pin games-like shooting bowing pins and other heavy objects to knock them from a table require very heavy bullets and near maximum charges. Hunting uses range from very light to very heavy in both powder and bullet weight-run in opposing direction, mostly.

To make a minimum power factor (floor) for COMBAT GUN GAMES requires that an average of some small number of bullets, shot under match conditions generate a number GREATER than the power factor (floor). One or two alibi rounds may be allowed, replacing shots generating a lower velocity and the computation redone, but results are definitive and irrevocable under the game rules.

Long story short: you need to DEPENDABLY generate a statistically derived small sample average power factor number greater than the power factor floor for all range and atmospheric conditions where you will compete. Shoot for an average power factor number of power factor floor + 10 or 175000. Until you gain some consistent statistical numbers on your ammo, load/shoot for 175000+ (i.e 175200 to 175800, typically).


You need a well recognized (as safe, sane and reliable) source of information. Universally, there is good agreement that the Speer Reloading Manual (12,13 or 14) is the most up to date and accurate.

All the lead bullet loads (except certain hand cast hard 44mag loads)for typical defensive caliber handguns (9mm, 38/357, 40/10mm, 44, & 45) are TARGET LOADS-soft lead. Conversely all jacketed loads are combat or defensive except where noted as 'HUNTING' (which are intended for creatures heavier in weight and construction than humans).

Your data lies between these extremes. It's not listed but it is implied in the forward text strategically placed about the manual.

To achieve a 'combat' loading in 357Magnum that just exceeds the major(IPSC/USPSA) or ESR(IDPA) power factor floor you must use a hard cast bullet (Missouri Bullet, Meister, etc) and extrapolate data between target loads listed and a safe weight 0.5 to 10. grains below charge weights listed for a similar weight jacketed bullet; both using the same powder. Hard cast lead does NOT make for a good defensive ammo-its strictly a gun game lower priced alternative. The Missouri Bullet website lists and demonstrates the required bullet hardness for a particular bullet velocity target; this hardness number can be compared against other bullet makers if they reveal their hardness standards.

To do this deed efficiently and safely you MUST have a quality chronograph and you MUST be able to recognize the first signs of excessive pressure as exhibited in the spent casings.

Pay close attention to using the Speer manuals handgun data section (as opposed to rifle) when developing these loads. Pushing 158 grain (soft) lead with Unique at target velocities requires between 5.5gr(970fps/6inch S&W19) and 6.0gr(1035); 175000 power factor target is 1108fps. A 158gr jacketed bullet runs 978(6.9gr) to 1040fps(7.7gr UNIQUE). While neither pair of loadings meet your requirements the jacketed maximum is well above 1200fps), your probable combat loading for a hard cast bullet is 6.1 to 6.5 grains but under no circumstances should you exceed 7.2 grains of powder. YOU MUST CHECK AND INTERPRET YOUR PARTICULAR CASES FOR PRESSURE SIGNS AND ALL THE USUAL DISCLAIMERS APPLY-User assumes all risks.

Special Note:With other powder-particular newer 'Magnum' powders, there may be little or no significant gap to extrapolate across and in fact, these powders may make 'major' with a target loading IN YOUR GUN.

Personal Note: I've competed in both events, but stopped some time ago. Rules change and there is something about 9mm being restricted to minor power factor in USPSA/IPSC-38/357 can be 'called' 9mm so a check with current competitors and IRO types in USPSA should be made prior to pushing 357 to major power factor-it may not be legal for competition.
 
I've used 4.8 grains of Titegroup with a 158 grain plated bullet. Should easily get you the velocity you need and provide decent accuracy and still be a "mid-range" mag load.
 
Unique will do it. Not guessing. Done it. Out of a friends 4" S&W M-66.
your probable combat loading for a hard cast bullet is 6.1 to 6.5 grains but under no circumstances should you exceed 7.2 grains of powder.
Looks like a winner. Wish i had my old Chronograph. Load 4 different bullets with the same powder charge of Unique. See what the FPS are between a plated, Cast lswc, swaged lswc, and Jacketed. I wonder?
 
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