Unique Loads in the .357 mag?

[Grmps]

And I gotta ask what mold is that RNFP? That is a great looking bullet.

that looks like lee's 358-158-RF

[Larry Gibson]

My Unique load is 7.5 gr. with 158 RNFP.

The SAAMI MAP (Maximum Average Pressure) for the 357 Magnum is 35,000 psi. I have measured the pressure in a Contender test barrel of 7.5 gr Alliant Unique under a 358477 (150 gr) in Winchester cases using WSP primers at 37,300 psi. I shot that load for years but now consider 7.2 gr Unique as a maximum load. Just food for thought.

Larry Gibson

[bluejay75]

I do not share load data that is not published due to liability issues. Please understand I am not trying to be a jerk...but it is a crazy world out there.

A Maximum load with the 158 gr bullet (Lyman source) is 5.1 gr in the .38 Spl. It is always wise to start lower...at say 4.0 gr and work up looking for signs of pressure. In a .357 Mag, it would be possible to go past 5.1 gr in the .38 case, again looking for signs of pressure. The danger in doing so is that if an overpressure load (for the .38) finds its way into a gun for .38 Spl only, it may be dangerous. The risk of mixing up loads may be minimized by marking the bottom of the cases with a felt tip marker...but only you will know its significance. So, generally the advice is to never load above the rated maximum for the case/caliber.

I believe there is no difference in the .38 or .357 case except for OAL. Therefore the case itself is safe at higher pressures. DO NOT use .357 Mag data in a .38 case as the reduced case capacity will spike pressure.

You have a low post count so I am not sure of your experience. Do not use any load data that you cannot verify in a loading manual or on the manufacturers web site...there are idiots out there. Forgive me if I had stated the obvious.

I have a low post count and I AM A ROOKIE RELOADER (less than 3 years)! And a more rookie of a caster (less than 1 year)!

I do know that Unique makes a very consistent load and with proper work-up and testing I should see what the MAX is in my gun.

I want to shoot the Lee 358-158 TL unsized and powdercoated in 38 special cases in a Chiappa Skinner Carbine with 6-6.5 grains of Unique if I get no pressure signs.

No offense taken, sir.

[bluejay75]

After an evening on the range to answer some questions from this thread, I learned a few things. Bullet Lee 358 158 SWC TL loaded in assorted 38 special cases with Unique powder and SPP.

1. I think I found my low charge weight, 22 lr replacement load.
2. Up to 6 grains of Unique wont flatten a small pistol primer.
3. Shooting charges from 4.5-6 grains, 5 grains was most accurate (10 shot group at 50 yards).
4. Shooting into freebore (rifle is rechambered to 357 MAX) bullet diameter should be as big as will chamber in your rifle.


Question: If Im not flattening primers, how do I know Im at max pressure?

[jetinteriorguy]

Another sign of over pressure in a revolver is difficulty in extracting cases from the cylinder.

[LAGS]

Today My Girlfriend shot up 100 rounds of .357 that I loaded for her Henry rifle that I bought her.
They were the Lee .358 Round Flat nose sized to .358 and Powdercoated with Smokes Traffic Orange and Signal Blue.
I used 5.5 and 6.0 of Unique and they wer both pretty accurate.

[Larry Gibson]

bluejay75

"Question: If Im not flattening primers, how do I know Im at max pressure?"

Odds are you won't know. Primers, even pistol primers don't really flatten until well over SAAMI MAPs. Same with "sticky cases....that happens well over SAAMI MAPs in most quality revolvers. Best to just stay within credible load data in newer manuals.

Larry Gibson

[Herb3]

For .357 Mag I have been using the Lyman 358430 (195 gr) over 5.5 gr of Unique here with good results in a 4" 686.

[Grmps]

.358-158-swc/358-158-RF: 38 special 4.6 gr unique, 357 mag. 6.4 gr unique = ages old recipee

[30ROUNDCLIPAZINE]

Glad this thread was brought back up. Saved me from doing it myself! Have a bunch of Unique, so I'm planning on using it for all my 9mm, 40 S&W, 38 Special, and 357 Mag loads.



As someone who's yet to cast a single bullet (although that should change next weekend!) I'm confused by this alloy. Seems like the pure lead would soften the COWW, and then Lino was added to harden it back up? Edjumicate me.

He's most likely using the soft lead to stretch out his WW supply and because he has it. The Lino was most likely added for its high tin content to help with mold fill out(least that's what I would've done), and yes to gain hardness back from using the soft lead. Usually the term "sweeten the pot" is referring to adding tin to your bullet alloy. FWIW I've shot full house 358429 loads out of my gp100 with straight coww with a little pewter for tin, powder coated and sized .001 over CYLINDER diameter with absolutely no signs of leading. Lino is hard stuff and completely overkill in any pistol rd IMHO even though lyman recommends it religiously.

[jonp]

Lee shows 5.3gr under a 158gr cast at 922fps with a max of 6.0gr

[Mr_Sheesh]

Minuteshaver -

If I shoot 100 rounds of 130 grain fmj Remington 38 special, and merely open cylinder and have them fall out on their own when I tip the muzzle up pressure is all good?

If I shoot standard factory federal jsp 357 magnum and need to use the extractor rod to get the empties out, that's bad?

Freely falling out = low pressure, which is OK.

Having to use reasonable finger pressure on the extractor rod is fine too.

BUT: If removing the cases from the cylinder requires use of a mallet on the extractor rod, loud screaming, a trip to the gunsmith or factory, or the like, you WILL want to back off on pressures! If you try to remove them and there is any doubt of being able to, the pressure is high. Think "If I was shooting back at people who were trying to shoot me, would I want extraction to be this hard?" if there's any doubt. Best to be easy on our firearms, too high of pressure is definitely bad.

(In case you haven't seen purple text before, we use it to be sure others know we're teasing / using humor. I do tease a LOT! Trying to get the idea across with a smile.)

[Kosh75287]

I reloaded 8.0/Unique/158gr. LSWC for a friend who owned a 5" S&W M27. It shot accurately and hit hard, even out to 100 yards, but leaded the barrel somewhat. We backed off to 7.8/Unique/158gr. LSWC, and lost very little. My Ruger Police Service Six and a friend's Ruger Blackhawk also digested these loads well, but I would be hesitant to use them in less robust revolvers. I finally settled on 7.6/Unique/158gr RNFP for a "general purpose" .357 load. From my 4" PS6, it delivers 1200 + 20 f/s, depending on whose RNFPs I use. Another powder to consider is Alliant Herco. It tends to give slightly better velocities in short (under 6") barrelled .357s than Unique, with charge weights that are 6 to 10% higher. Good luck!

[Walks]

I tried that 8.0grs of UNIQUE load once under a #358156GC cast of pure LINOTYPE. I was out of 2400.

Primers flattened in both a NM Blackhawk & a M27. Case extraction was a bit sticky. Never used that load again.
6.5grs of UNIQUE under the #358429 is my favorite
.357mag Target Load in every .357Mag Handgun I've ever owned except the M27/28.

And yes I've used pure LINOTYPE on every Gas Checked bullet for 60 YEARS. Never had a leading problem because I size according to each gun/cartridges needs.

I even used that #358156GC cast of pure LINOTYPE over a then max charge of 2400 to take a Cougar treed by hounds in 1970. The exit hole was the size of a quarter. He dropped out of that tree stone dead, limp as a dishrag.

And I use still UNIQUE for .38/44 loads in COLT SAA's & Official Police & M23's.

[curioushooter]

Thanks for chiming in Larry. 8 grains of Unique seemed definitely over pressure against today's standards with a 150 or heavier bullet.

7 grains seems to be about what a 158 seated to 1.590 would max at. Alliant has 7.7 grains as a max with a Gold Dot.

[Three44s]

With magnum revolvers when I want more horsepower than a mild medium load fueled with Unique produces, I reach for HS6.

HS6 is a spherical powder, it meters smoothly and consistently. Unique varies greatly in charges out of powder measures. If you are pushing the max pressure range with Unique and throwing those charges and not weighing them you are asking for trouble IMO.

Furthermore, HS6 is a somewhat slower powder than Unique. As such you will deliver more velocity at a lower pressure at the correct charge range than you can with Unique. Richard Lee wrote in his load manual about the strength of lead alloys and found that peak pressures in the mid 20k range fit our average lead alloy strengths better than trending into 30K plus do. When you push Unique, those loads run into that upper range pressure rather quickly.

I am still a big fan of Unique but as I raise the power level above where it works best I switch up to HS6. I use and have used HS6 in .38 Specials loaded for .357s, .41 and .44 Mag. I have used it similarly in the 480 Ruger and in all cases it has delivered good and consistent results.

I have had good performance from this powder in 9 mm Para and 7.62 X 25 mm as well.

Three44s

[gwpercle]

I've been using my 0.7 cc Lee dipper for years w/ 158 gr SWC's- seems that is now considered a bit warm, as it translates to 6.4 gr. Unique- my rugers like 'em, though, and I'm staying with it.

The 1970 Speer #8 manual , 357 magnum , with 158 gr. Speer LSWC / Unique , listed as a starting load 7.0 grains @ 1149 fps ...
with a max. of 8.0 grains @ 1257

Wanting to be a safe reloader, I loaded them with 7.5 grains Unique @ 1200 fps...or so I thought.
For the next 30 years I shot that load in a Ruger Blackhawk ... Thank Bill Ruger for making them on the stout side . But I never had any sticky extraction so assumed Speer knew what they were doing...Until I bought the RCBS Manual #1 and noticed the Max load was now only 7.0 grs. , the start load was now 6.5 grs. !!!!

That 6.4 grain load should be OK , at least according to Speer Manual #9 !
Gary

[gwpercle]

The Skeeter Article on the .357 which lists light, medium, and heavy loads can be found here:
http://www.darkcanyon.net/MyFriend_The357.htm

If you have any interest at all in the 357 magnum this is one of the best most informed articles you will ever read . Print the 8 pages and keep them with your reloading manuals . I have it somewhere but printing it again...you can't have too much good information when reloading .

Thanks Thomas....
Gary

[cowboy4evr]

I have tried many 357 magnum loads using the Lyman 358156 ( the Ray Thompson 2 groove swc) and the Keith 358429 . I have found 7.5grs of Winchester Super Field a really nice upper mid range load with the Thompson design bullet . It shoots very accurate and the brass is clean . I had Tom @ Accurate Molds make my molds plain base instead of gas checked . 9.5grs of HS6 gets use as does 10grs of Blue Dot . Regards, Paul

[Porous casting]

Dragging up an old thread ,new to casting, Have bought lee 105 swc and 125 rf.to use in gp100 357 6"and sti spartan 9mm.
have unique and wsf powders and a new bottle of aps350,
have been shooting with around 4g with wsf in the 9mm and unique with 38spcl .
wondering on loading up some stouter loads in 357 cases with the 125 rf (around 128g drop)
have been powder coating with Eastwood powders. But usualy spray with lanotec when I size them
I have been thinking about 6 or 7 grains of unique.(would like to get a 357 rifle also)

any help /pointers would be great.