357 Mag loading mystery

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rck281

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I have been trying to develop an easy shooting load for my 357 Mags. All loads were developed using Remington cases and CCI SP primers with 158gr JHP Montana Gold bullets. I seem to get very inconsistent velocities as indicated below:

Wtg. Powder Gun Vel. Variation SD
5.5 Unique Ruger 4 5/8" 891 28 12
6.0 Unique Ruger 4 5/8" 937 88 35
6.5 Unique Ruger 4 5/8" 1003 109 39
7.0 Unique Ruger 4 5/8" 1061 74 25
5.5 Unique M27 - 5" 803 173 71
6.0 Unique M27 - 5" 891 109 35
6.5 Unique M27 - 5" 978 84 30
7.0 Unique M27 - 5" 1059 38 13

Although Alliant lists 7.7gr of Unique as maximum for a velocity of 1040fps with Speer 158gr Gold Dots, I get a higher velocity using 7.0gr. I have also experience several pierced primers at the 6.0 and 6.5 gr loads but never with a 7.0gr load. I just don't understand my results.

What do you guys load with Unique and 158gr jacketed bullets?
 
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I just don't understand my results.
Click to expand...

Which is why I don't use unique for light loads in large cases.
My quick solution was to use HP38/Win231.

Several possibilities:
1. Metering. Unique is not know for consistent metering through all volumetric powder measurers. You may be getting large variations in amount of powder.
2. Chrono technique. Light loads in large cases need to be positioned consistently for each shot, preferably with the powder to the rear against the primer. Raise the muzzle and level for each shot. As much as 100 fps less if powder is positioned forward.
3. Unless you have to make a certain power factor and just have to use Unique, then evaluate the targets. If the vel variations don't show significantly on target, then ignore the chrono results and just go shoot. My .45 ACP loads with Unique are that way. Large vel variations, don't show on target. Just can't risk DQ for power factor in competition, but plinking, who cares?
 
With the 158gr JHP bullet I did not get good results with Unique until I hit 6.5grs or more. It did its best work at the top end with the cci 500 primer at around 1240 fps in my 6" mag.

I never got the large jacket bullet to do well in my revolvers with light loads........... light to medium velocity loads had to be lead bullets, for me with w231 or faster powders for best accuracy.

Good luck.
 
I use 7gr of Unique behind a 158gr LSWC, Most accurate out of my 357's ; )
Y/D
 
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I use 7.5 gr of Unique under a 158 JHP. It's accurate while being a pleasant load to shoot, not only in the revolvers, but the .357 carbine.
 
max said:
I think you are wasting money using jhp's for such light loads.
Click to expand...
That may be true as these are $12.55 per 100 but they aren't a great deal more than lead. Also, I have about 2000 and have shot all the lead I had. That's why I'm developing a JHP load.
 
buck460XVR said:
I use 7.5 gr of Unique under a 158 JHP. It's accurate while being a pleasant load to shoot, not only in the revolvers, but the .357 carbine.
Click to expand...

I use 7.5 grains of Unique behind a 158 gr. swc lasercast
bullet. Pleasant to shoot and good accuracy.
I also find Unique to be inconsistent to meter out of my Redding powder measure so i weigh each round using a trickler.
Hope this helps.

Chuck
 
357 & Unique

rck281 said:
I have been trying to develop an easy shooting load for my 357 Mags. All loads were developed using Remington cases and CCI SP primers with 158gr JHP Montana Gold bullets....
I have also experience several pierced primers at the 6.0 and 6.5 gr loads but never with a 7.0gr load.
Click to expand...

I don't see a reason why you'd get pierced primers with loads that are half max pressure, unless it's a firing pin issue. Did that happen on both guns?

The Ruger seemed a little happier with the light loads than the M27 (variation/SD). As far as your velocities not matching Alliant's I wouldn't let that bother you.

I've used loads similar to yours without issue. Did you measure the powder individually or throw it from a powder measure (different style measures are more consistent than others with Unique)?
 
rck281 said:
I have been trying to develop an easy shooting load for my 357 Mags. All loads were developed using Remington cases and CCI SP primers with 158gr JHP Montana Gold bullets. I seem to get very inconsistent velocities as indicated below:

Wtg. Powder Gun Vel. Variation SD
5.5 Unique Ruger 4 5/8" 891 28 12
6.0 Unique Ruger 4 5/8" 937 88 35
6.5 Unique Ruger 4 5/8" 1003 109 39
7.0 Unique Ruger 4 5/8" 1061 74 25
5.5 Unique M27 - 5" 803 173 71
6.0 Unique M27 - 5" 891 109 35
6.5 Unique M27 - 5" 978 84 30
7.0 Unique M27 - 5" 1059 38 13

Although Alliant lists 7.7gr of Unique as maximum for a velocity of 1040fps with Speer 158gr Gold Dots, I get a higher velocity using 7.0gr. I have also experience several pierced primers at the 6.0 and 6.5 gr loads but never with a 7.0gr load. I just don't understand my results.

What do you guys load with Unique and 158gr jacketed bullets?
Click to expand...

Unique is a bulky powder but these are still pretty light charges for the .357 case which means the powder position can and will vary from shot to shot...with the lower charges having the powder oriented farther away from the primer...which may account for enough of a pressure spike to blow a primer at a mid-charge versus a heavier charge where more of the powder is likely in front of the touch hole. Also consider tough hole size...even within "brand" touch holes can vary in size and a larger touch hole will allow more pressure to bear against the primer cup.
These are pretty light loads for a .357 case...you'd be better served using .38 Spl case for all your "light" .357 loads. Not only does it make it easy to "know" when you shove a .357 case in your revolver you are shooting a REAL .357 level load, but it also makes BETTER use of small powder charges.
I've used Unique since I was knee high to a Dik-dik, and have NEVER had pressure signs in any .38/.357 case so maybe...just maybe you might examine your firing pin for excess protrusion....doesn't take much extra, and the combination of factors is what causes the pierced primers...
 
rck281 said:
That may be true as these are $12.55 per 100 but they aren't a great deal more than lead. Also, I have about 2000 and have shot all the lead I had. That's why I'm developing a JHP load.
Click to expand...

You can order 158-grain lead semi-wadcutters in target hardness (#358158S) or magnum hardness (#358158M) from Missouri Bullet Company for $35.00 per 500. At $7 per hundred, I call that "a great deal" less than you paid for those jacketed bullets and MBC ships in USPS Flat Rate boxes, so you can have 1,500 bullets shipped to you for $13.

As hard as reloading components have been to find in some parts of the country, you might want to try selling them and replacing them with lead.

Ed
 
If you just want to use Unique you need to go to near maximum loads to get your best accuracy.

If you are not happy with what you get, you need to get a pound of 2400 powder to try out for some " medium to maximum loads" with just standard primers..............
it worked for my 158 Jhp bullets.
 
I never used Unique powder in my .357 loads. The best 2400 load that worked for me is 12.5 gr 2400, CCI mag primer, 160 gr lcswc. This load is accurate in my guns but kinda dirty.

The one load I found that I favor the most and have shot thousands of rounds is 15 gr WW296, CCI mag primer, 160 gr lcswc. This is the most accurate for me. To me the WW296 powder is hard to beat for .357 mag loads.
 
With a 158 grain Jacketed Hollow point....7.5 grains of Unique.

In my old model Ruger Blackhawk it would group 6 shots into nearly 1 hole at 25 yards. Stop paying so much attention to FPS and find a load that is the most accurate.
Velocity varies so much from one gun to the next, loading manuals at times use universal recievers to get data...thats not even a real gun only a test fixture.

This was Skeeter Skeltons favorite load using Unique , a general purpose tin can and rabbit load., His max. hunting, deer big game load , used 2400 powder and was a bit warmer.
Gary
 
The pierced primers with 6.0 and 6.5 occurred in 3 guns - the two shown with chronograph data and my 686. Never with 7.0 gr. All cases were R-P that have the same number of loadings - 3. The ammo used for chronographing was assembled using a RCBS powder dispenser (I need to look at this - maybe this is throwing inconsistent loads). The cost of my Montana Gold bullets includes shipping. Adding shipping to the MBC bullets brings them to around $9 pre 100. I use MBC in my 44 Special and 45 Colt and they are excellent bullets.

The question is - why pierced primers with 6.0 and 6.5 but not at 7.0 gr of Unique. Need to look at the powder dispenser - hadn't considered it.
 
Unless you hand weigh every charge, Unique is to inconsistent in how it measures. I would look to another powder that measures better. My go to powder is 231.
 
H Richard said:
Unless you hand weigh every charge, Unique is to inconsistent in how it measures. I would look to another powder that measures better. My go to powder is 231.
Click to expand...

While there may be a slight variance to Unique's weight when using a measure, Unique shoots very well when measured by volume. One reason it is a favorite of those that use dippers to reload. There are many opinions on the subject, but many argue that powder charges by volume are just as, if not more accurate, than powder charged by weight. I use a baffle and the "double tap" method of dispensing and have found Unique charges thrown by volume work just fine and are every bit as accurate as W231/HP38.
 
I like 231/HP38 for range loads as well... because I can use it in all of my handgun calibers (9mm, .38, .357, .40, 9x25 Dillon, 10mm, .45acp, .45 Colt). And it meters almost perfectly every time.
 
nebmike said:
I like 231/HP38 for range loads as well... because I can use it in all of my handgun calibers (9mm, .38, .357, .40, 9x25 Dillon, 10mm, .45acp, .45 Colt). And it meters almost perfectly every time.
Click to expand...

What manual are you finding .357 loads using 231/HP38 ?
 
rwsmith said:
May I ask what these bullets are and where from??
Click to expand...
The bullets are Montana Gold. I use Montana Gold bullets for my 9mm and 40S&W. A friend wanted to split a case of 2950 bullets for $370 with free shipping. They make excellent bullets in my opinion.
 
Dick, I have also had pierced primers. When one does everything correctly and this happens time after time with a certain load, I think one can just figure it's the nature of the beast and move on. The pressure isn't too high, it isn't too low, it just happens to be perfect to make things just right to pierce a primer. I can't figure out why, it just is.
I think your on the right track with the Montana Gold Bullets. They are just about as economical as some of the store bought lead bullets. Not quite as economical, but darn competitive for a jacketed bullet. I recently purchased a bunch in .357 and .44 and found the quality and accuracy outstanding.
Any way.... Just my two cents.

Chad
 
I have been working on a load for 357 magnum with universal clays. I use six grains of universal and a 158 grain bullet.lrnfp I would never consider this a magnum load it is very nice shooting. I use 2400 for real 357 loads
 
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