starting charge-357 mag


January 4, 2008, 01:42 AM
New member looking for some guidance. Trying to load 357 mag.Im using start data from Speer 14 with AA#5 and Win 231 powders, Win small primer, 110 jhp (.3565). Gun is Taurus 669,6in bbl w/vent rib. Primers are flattening out and extraction difficult with start charges. I've found other sources, Hogdon site, md smith and handloaders online, they show max loads right around the speer start loads. Could the Speer book be that high on the start loads? For this gun I assume so, should I be looking for other issues? Just never had an issue with other loads out of Speer book. Thanks in advance,

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January 4, 2008, 02:26 AM
Welcome to the forum.!

pls list the loads ur using so we can do some chekcing on our end.

Steve C
January 4, 2008, 02:28 AM
There are several reasons for sticky extraction, only one is over pressure. Rough or dirty chambers are two others. When you say the primer is flattened how are they when compared to a factory round?

You don't say if your Winchester primers is a magnum or a standard small pistol primer. Winchester magnums are quite hot and will push pressures up. Accurate Arms load data had a note in it to consider the start charge the maximum if using Winchester Small Pistol mag primers.

Here's a picture of fired .357 mag cases. Only the one on the left is flattened and shows a bit of cratering. The others would be considered normal.

January 4, 2008, 02:33 AM
I have found some of Speer's data to be way to hot, I would get another load manual or two for cross reference, Hornady or Sierra and Lyman would be good. There is a lot of on line data available as well, Google most any powder makers name to find it.

January 4, 2008, 08:38 AM
jibjab: can you elaborate on this? Mind you, I do NOT have #14 yet (in fact, I'm going to buy it today, as an early birthday present to myself)--but as you know, I've worked extensively with the Speer 38+P data for the 135-gr. Short Barrel JHP bullet.

Here's a "pressure recap" for us to consider:

1. Speer worked up its specifications for the Short Barrel Bullets about 2003. They used 20,000 PSI as their baseline for MAX pressure.

2. Since then SAAMI has reduced the "+P" max pressure for 38 Special to 18,500.

3. Originally, 357 Magnum maxed out 46,000. Over the years, that max has been reduced 35-36000--Hodgdon currently uses 35,000, IIRC.

Ostensibly, these industry-recommended standards (SAAMI is NOT a regulatory agency) have been adjusted for various reasons. One is simply using more uniform / broadly-accepted testing protocols with less subjective interpretation. Another is the availability of testing methods that gather more precise data about the pressure 'experience'--the observation of three pressure curves, for example. A Third, and most assuredly the most problematic, is the subjective evaluation of "safe" pressures in light of business policies--the Legalese CYA syndrome, so to speak.

Now, back to the subject at hand--those 38 / 38+P load recipes Speer gives, and Steve896's experiences with them in his Taurus. SASS#23149 is right--give us the recipes you are using, so we can check them.

I'm going to assume you've eliminated error on your part--e.g., your scale is accurate, your LOA is correct, etc., etc. In sum, it appears that, for whatever reason, these may be too hot for your firearm.

My own experience with AA#5 and nominally the same components (I use the GDSB135JHP bullet, and 140LTC bullets) is that pressures nominally match what Speer reports. However, #5 is a fairly "fast" powder--and I would suggest you also consider loading #7 if you're going to be shooting in longer barrels.

I tried 231 early on in my "replica loads" reloading project, but I set it aside as it peaked very fast and was suitable only for low (bullseye-type) to medium pressure loads. At higher charges, the case bulges quickly (and that's with new Starlines).

The early reloads included 105-gr LTCs, Win 110-gr JHPs, and both Lead and Win(?) 125s--and I quickly moved away from fast powders and light bullets for 38 /357 max loading--the pressure is simply too quick.

FWIW, I had a 38+P "overpressure incident" last summer--arguably, 55,000-72,000 PSIs on a cylinderful of reloads. Even those primers did not look "really" excessive--and the extraction was real sticky; two cases had head separation. Fortunately, the firearm used was a 357 frame (S&W 640), so no blowup occurred--but the cylinder was damaged.

As a result of that experience, I now relegate primer reading to the value of finding the future by looking at goat entrails obtained at midnight on a moonless night. (I suspect some value can be obtained from primer examination, but only on a very-gross level; precision requires too much data keeping for one particular firearm.)

Similarly, I wonder about 'sticky extraction' as a reliable indicator--particularly if 38 Special has been fired in a 357, with the notoriously-difficult-to-remove crud ring buildup when its done.

So, tell us more, steve896.

Jim H.

Jim Watson
January 4, 2008, 08:44 AM
I got sticky extraction (from clean chambers, yak, yak, yak) trying to get up to Major Power Factor (158@1130) with fast burning powders, including Win 231.

That just isn't the way to go about it.

January 4, 2008, 09:38 AM
Thanks for the replys, sorry for leaving out info. The primers flattened out,looked kind of mushroom head like on top when popped out. I used std Win primers, set bullet to oal 1.575. I used starting chg of 10.8 of AA#5 and 8.5 of Win 231.(this is the powder I have on hand at this time). Barrel is clean, I haven't shot any 38 spl in it. I have checked other load info and thats where I see lower starting charges. But how do you determine if someones start is too low or too high?

January 4, 2008, 10:37 AM
I just checked your loads against my (mfr) sources--AA, Hodgdon

1. 10.8 gr. for a 110-gr. Speer is the start load in AA 2004 manual.

2. Hodgdon currently rates the Hornady 110-gr. XTP from 8.0 to 9.0, so your 8.5 gr. of 231 start is, their standards, "midrange"--with a different bullet--and with that bullet the LOA is 1.590.

If I were pursuing these two powders with this bullet, I would back up both loads 10% and try again--but, essentially, I'm with Jim Watson. I'd reserve 231 for lowball-light loads, and I'd explore more with #5--i.e., try a reduced load. Did you double check your scale? Have you got a second scale, or a set of checkweights for calibrating?

FYI, here's a link ( what my primers looked like after that overpressure incident.

I would describe these primers as flattened and cratered--but not excessively so, and there is no 'flow.' If your primers look flatter--or like they actually "flowed" in the primer cup, then your pressures are awfully high.

It might be a gunsmithing problem--but I gotta wonder about scale accuracy (at least for this batch). If you have any rounds left, disassemble a couple and re-weigh them.

Was there sticky extraction on ALL the rounds? if extraction seemed to get progressively worse, you might have been dealing with bullet jump (which is an indicator of a weak crimp).

If you can post a picture of the primers, that would give us some more information--but I would NOT shoot any more of those rounds IF I had not found the error. In my incident, after shooting the one cylinderfull, I took the remainder home, disassembled them, and looked for the source of the problem. (In my situation, it a was piece of paper holding the scale tray--and I had missed seeing that--so my 38 special cases had about 17-18 gr of #7 in them, and it was NOT a 'double-charge' error.) At the time I built the rounds, I was not experienced enough with #7 loads to recognize the awfully-full case....which is a situation not too dissimilar to your situation.

The point is, find the problem before you shoot any more.

Jim H.

January 4, 2008, 12:39 PM
Jim H:Not sure if I can get a pic uploaded yet, but my primers look like the ones in your link flat but not cratered. All loads were trickled and weighed, the scale is a rcbs505, check weights were used to verify as close to final weight as possible. BTW, i'm only looking for target/plink loadings for this gun at this time, I will back up both loads 10% and try again on Sunday.

January 4, 2008, 01:44 PM
You still haven't told us what brand of bullets you are using?
Speer or something else?

January 4, 2008, 02:21 PM
sorry about that, bullet is Remington 110g semi jacketed hp from Midway.
Question:is it ok to add info as a reply post in this forum or should i be editing the original post.

January 4, 2008, 02:32 PM
There's no issues with adding on, Stever. As for the recipe problem--I am still stuck at the correct-weight issue--can you borrow another scale, or whatever, and double-check again?

You have cleaned your Taurus, haven't you? I mean REALLY cleaning the chambers and barrel? I'm just casting about here, though--nothing really new to add.

Jim H.

January 4, 2008, 02:39 PM
The charges you report shouldn't cause an over-pressure problem but obviously you are having a problem.

Might there be an obstruction in the barrel of your gun? Try shooting a cylinder of factory rounds and see if the primers flatten out with the Factory rounds too.

If you are looking for plinking rounds you really don't need to load them to Magnum pressures. (unless you like the kick) If you don't want the kick and really want a plinking round then all you really need to do is load your .357 Magnum cases with .38 Special load data. As a matter of fact, you can use .38 Special Brass and save the .357 Magnum Brass for when you want a full house round.

January 4, 2008, 02:54 PM
I have to agree with those who pointed out that 231 & AA#5 are not the best choices for .357 Mag high-velocity plinking loads in a 6" barrel revolver.
They are both very fast powders, and any slight variation can cause pressure spikes all out of proportion to the velocity you are getting.

Even starting loads of Unique, Power Pistol, 2400, and H110 will give 100 - 300 fps higher velocity, at much less pressure.

January 4, 2008, 03:04 PM
I completely agree with rcmodel, a slower powder's starting charge will out perform the Max charge from a faster powder in a .357 Magnum.

From the Hodgdon site:
W231 - Max 9.0gr - 1652 fps - 42,500 CUP
W296 - MIN 22.0 gr - 1992 fps - 32,400 CUP

You will get much better performance from a powder more suited for Magnum rounds than the faster powders you are using. You can add Longshot and H4227 to the above list rcmodel gave you.

The Bushmaster
January 4, 2008, 03:21 PM
Steve896...First of all. Flattened primers do not indicate an over pressure load. Most moderate to maximum loads in .357 magnum will exibit flattened primers. Now if the flattened primers are cratered, pierced or show blow-by around the edges then you can say "over pressure"...

I have not played with 110 grain bullets, but I can give you an insight to W-231. I have used it in my S&W 2 1/2" mod 19 for years under a 140 grain SJHP. My intentions when I started was to get or excede 1100 fps from this short barreled revolver using the 140 grain bullet. I made it 1150 fps using 7.8 grains of W-231. At 8.0 grains I started having difficulty ejecting the cases. What I learned about W-231 is that it tends to increase pressure explanatualy per.1 grain increment then most other powders. If you start at the low end and work up by.1 grain until you start to have ejection problems and reduce it by .1 to .2 grains you would be fine.

Remember that fast burning powders tend to work better in shorter barrels and slow burning powders tend to work better in longer barrels. If you have a 4" barrel or longer I would recommend Alliant 2400, W-296 or Hodgdon H110...

One other thing...Is that Taurus brand new? If so...You may have some machining left in the chambers...That, in itself, would cause a whole bunch of problems until it wears in or get a good lapping...

January 6, 2008, 08:38 PM
To answer the a question from previous posts, I did check my scale against another and with the check weights, scale weight matched check weights,both scales the same. The other quest. was on the gun, not new but only 2-300 rounds thru it. Back to the range today, had reloaded a couple rounds , (110 rem jhp with 9.7g of AA#5 @1.575 oal - 10% less than 1st loads.) and shot factory (rem 125g jsp) to compare primers. Reload recoil/extraction ok, primers still appear flat(to me) though the factory rounds looked ok. (reloads on left of pic). Will pursue a more suitable load for this gun, I was just trying to use what I had on hand at this time. Recommendations welcome! Thanks for the replys and info.

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